# "Local device name already in use" error



## JT Cole

I am at work on a new computer running XP Service Pack 2 and I'm having problems connecting to our server. When I try to go to these drives I get the message "Local device name is already in use. " "This connection cannot be restored." These shortcuts worked yesterday which was the first day I hooked this computer up, now they don't for some reason. Our "IT" people don't know a whole lot because they are really just our accounting department so I'm trying this route. Also, I can still access the internet and email which is routed through our network just not the network drives.


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## 5mi11er

Did you disconnect the laptop from the network, put it in standby mode or hibernate, (for instance to take it home), then come in and simply reattach and unlock the computer? If so, the Domain Controller (aka Active Directory Server) has probably forgotten your credentials. Try to logout, then log back in, or deleting the shares and reconnecting to them sometimes works as well. If those don't work, try rebooting.

-Scott


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## marklab

Sounds like the computer is trying to map a drive that already exists. Go to, "My Computer" then look at the drives there. If any of them have a red X right click them and click disconnect.


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## JT Cole

I already rebooted and logged out and back in and all that but none of it worked. This is not a laptop, its just a regular desktop computer. Also, I checked to make sure that no local drives had the same drive letter as the drives on the server. I suspect that it is something along the lines of the server forgetting my credentials, so how can I fix that?


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## JT Cole

One more thing I have tried that I thought I should mention. I disconnected from the drives and was going to re-map them. When I went to My Network Places I get an icon for our local group but no drives. Since their are no drives to map, I can't re-map them. I guess that makes sense since I can't connect, but this is almost like I'm not really logged on to the server. When I start up I log on as usual and I get no error messages or anything but something is definitely not right.


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## 5mi11er

You don't have to see the drives in order to attempt to map them, you just need either the server name and share name or the ip address and share name. 

You might try "finding" the machine name that the drives are on, if you can find it, the drives should show up...

But, if you're supposed to be logging into a domain, but you're currently not, then I'd say you need to contact the admins, and get that box to login to the domain correctly.

-Scott


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## Flail128

You may have a cached session on the server still. Disconnect or turn off problem PC. 

Logon to server, control panel-->admin tools-->computer management-->shared folders-->sessions. See if your computer name is in there, if so, right click and disconnect. Refresh(Hit F5 key) and connect PC back to network.


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## JT Cole

OK thanks for the info, I'm gonna give that a shot


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## JT Cole

OK, the network administrator removed me from our network as a user then re-added me. Then, she logged me on from a 98SE computer on the network and it worked fine, I could get to the server drives and network printers just fine. However, when we tried to get to these resources on my XP system it wouldn't work. We tried to remap them through My Network Places but oddly when we went into the Entire Network ---->Microsoft Windows Network----->(our local server name) there was nothing. The computer names that should have shown up under our local network were not there. At startup, I logged on with my normal network password and didn't get any error messages, but for some reason I don't see any of the other machines on our local network. Whats up with that?


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## Flail128

Is your firewall enabled? Check Control Panel-->Windows Firewall and go to tab marked "Exceptions" and check that File and Printer Sharing is checked (allowed as an exception). You could also just disable the firewall.


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## Bob Cerelli

The error "Local device name is already in use" simply means that you are trying to map a network connection with a drive letter that already is assigned to some local device. 

That is why logging in on another computer worked. It didn't have the same local devices as your computer. 

You need to have your network administrator see what drive letters are trying to mapped, which local device already has one of those letters assigned, and give it a different local drive letter.


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## JT Cole

I have heard that this error should be because a local drive has the same drive letter as network drive and therefore the network drive cannot be mapped but I don't think thats the problem here. I only have A, C, & D drives on my system (No partitions, removeable drives, etc) The network drives are supposedly S, P, and U.


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## Bob Cerelli

Is the computer also trying to run a logon script that would make a network connection for one that is already there.

For example, if a drive letter is mapped through the Windows Explorer, and then the same drive letter is trying to be mapped through a logon script, you can get the same error.


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## JT Cole

OK that is a little bit over my head I think but it sounds like you might be on the right track. I do login to the network at startup and sometimes there is an error *before* I login when the login screen is up that says something like "A duplicate name exists on the server." Does that sound like about what you're talking about?


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## Bob Cerelli

Exactly.

An easy way to test this out and hopefully solve the problem (assuming you have a login script running) is to:

1. Open the Windows Explorer
2. Tools / Disconnect Network Drive
3. Note all the drive connections you have (just in case there isn't a login script)
4. Remove them one at a time
5. Log off and back on again


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## JT Cole

In one of my previous attempts to fix this problem I already disconnected and removed these network drives. The problem is now I can't re-map them either. When I went into explorer to disconnect (as I expected) it said there were no drives to disconnect. When I then try to remap the drives it shows the server locations ("\\Server\Users") but will not connect to them in order to map.


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## JT Cole

It would seem that the server is not recognizing me at all. I am connected to the router that we get internet through and that works OK but not the server side stuff.


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## Bob Cerelli

Would have been good to know this ahead of time. So if you can't map network drive to the server, what network connections are being made when you logon an how.

What were the network connections you have previously

What do the IT people say you should be connecting to

What are other people in the office connecting to.


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## JT Cole

Well I did say all of this earlier in the post:
"One more thing I have tried that I thought I should mention. I disconnected from the drives and was going to re-map them. When I went to My Network Places I get an icon for our local group but no drives. Since their are no drives to map, I can't re-map them. I guess that makes sense since I can't connect, but this is almost like I'm not really logged on to the server. When I start up I log on as usual and I get no error messages or anything but something is definitely not right."

If we had the IT people we should have I probably wouldn't be going through this so they aren't much help. We have three network drives we connect to, User, Server, and Public. I don't understand why I can login at startup and not get any error messages but when I go to Network Neighborhood there only shows our general network "Ada" and when I try to browse it (where I should see all of the connected computers) there is nothing. I really appreciate your help and tolerance of my networking ignorance... Thanks
__________________
"Pain? I AM PAIN!"
-Pinhead


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## 5mi11er

> A duplicate name exists on the server.


Have the admin's check to see if there's another computer that has the same name as yours does.


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## JT Cole

That has been done, and there's not


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## Julie Barker

Sorry about missing the previous post.

You won't see drives to remap but shares on computers. 

What do other people see on their computers when browsing the network.

If you had the same computer name or IP address as another computer you normally receive a wanting about this when you start the computer. 

Rather than relying on browsing, what happens if you manually enter in the computer and share name for a drive you want to map. You can again do this from the Windows Explorer


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## JT Cole

Next to "Folder" in the "Map Network Drive" I can put in the path that other people can see on their Network Places like ( "Ada" is the name of the local network I think)Ada\\Server\Public but it still doesn't find it. It is like I'm not even on the server at all


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## Bob Cerelli

The syntax would just be something like:

\\Server\Public

You can also try doing it from a command prompt

Open a CMD prompt ( Start / Run / cmd )
Then "net use x: \\server\public" - no quotes
Sometimes doing it this way gives and error that makes it a little easier to help find the solution.

What makes you think you are "not on the server at all". Your user account is not on the server? You don't have rights to any shares on the server?


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## JT Cole

When I do that at the command prompt I just get "The network path was not found" I don't have access to any network shares or anything. The only thing I can do relating to the network is get on the internet, other than that nothing. Thats why it doesn't seem like I'm connected to the server. The only thing I don't get is why I don't get any error message when I try to logon.


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## Bob Cerelli

Network Path Not Found and Not Having Access are two completely different problems.

If you can't find the network path, you don't even know if you have access or not. You can't even find either the server or share name

1. Open up a cmd prompt again
2. Can you ping the server by IP address (e.g. ping 192.168.0.x) or whatever the actual IP address is of the server
2. Can you ping the server by name (ping server)


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## lakecrowley

Hello

Has this issue been resolved because I am having the same issue with two
win XP pro computers in two separate domains and locations. You click on the shortcut or the drive letter and you get "Local device name already in use".

When you go to my network places to the server it prompts you to log in.
When you log in it says user is already logged in.

I have found the only way to get out of this is to log off and log back in.

One computer has service pack 1 and the other computer has service pack 2.

Thanks

Lakecrowley


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## iamageek

Hi,
i dont reckon this is the solution to your problem, but worth checking - i just had the exact same issue (without SP2, dont like it). I was using the wrong subnet mask - i had been on a different network yesterday and didint change it properly back, so i was using a /23 rather than a /16. Must have meant that certain network resources were accessible and others werent. Changed the mask and it worked fine...


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## Bob Cerelli

Since things have changed since the beginning, let's get back to the basics just to have a good starting point.

1. Make sure you have the same IP scheme (e.g. 192.168.0.x).

2. Make sure you have the same Subnet Mask, Gateway, and DNS IP addresses.

3. Make sure you can ping the other computer's IP address. If this fails, just for testing, make sure you turn off XP's as well as any other firewall.

4. Make sure you can ping the other computers by name.

5. Make sure you have the same workgroup name (watch for trailing spaces)

6. For troubleshooting purposes, turn off XP's and completely uninstall any other firewall software. You can always add more complexity after you get it working.

7. With XP, make sure you have the same username and password as the person logging onto the other computers. The default setting for XP Pro is to require a password for network access.

8. More details about how to network XP can be found at:
http://www.onecomputerguy.com/networking/xp_network.htm

9. More details about how to troubleshoot TCP/IP networks can be found at:
http://www.onecomputerguy.com/networking/trouble.htm

10. Apply the registry edit to fix the browsing delay from XP to Win9x computers 
http://www.onecomputerguy.com/windowsxp_tips.htm#browsing_delay.

There continues to be a lot of misinformation about needing NetBEUI or to changing the NetBIOS setting. You can ignore both. Installing NetBEUI to solve a networking problem will just mask a some underlying and potentially important misconfiguration with TCP/IP. The default NetBIOS setting works fine so there is no need to change that either.


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## paj692

undefined  
I have read this thread with great interest since the same thing has been happening to me. Let me assure you other quazi-know it alls that this is not a simple problem of having too many drive letters or failing to log out. Also, disconnecting the mapped drives and attempting to reconnect them may not help. This is an XP problem (not a feature). According to the microsoft Knowledge Base, it occurs because 2000, 98, and any OS before XP assigns drive letters from G upwards and XP assigns letters from Z downward.
They suggest renaming mup.sys in your system32\drivers directory to old and running sfc /scannow from a cmd prompt (i.e. start > run > type cmd <enter>)
This seemed to help, but the date and the filesize are the same. Occasionally I have had success running the network/internet connection wizards to resolve the problem. There are administrative (or administration) tools that can be accessed through the control panel and possibly the programs section of the start menu (if you installed it and checked that option). I was able to restart the RPC (remote procedure Call) under services(local) on the admin. tools console. The next time I tried it there were no options for start/restart in the upper left and no way to change the configuration. Although recently I badly corrupted my admin tools and couldn't find instructions on how to fix it.
Please don't suggest I re-install fresh. I have alot of stuff on my system and it works most-of-the-time.  Anyway, I've already told you more than I know. BTW I have a simple home network. two machines through a router and out to the internet via DSL modem. One machine is XP and one is 98SE and they are both desktop models. If anyone has a stone-cold fix to this (which isn't 'have you tried turning your machine off and then back on'), I'd sure like to hear it. Thanks muchly PAJ


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## Bob Cerelli

It's good we have someone like you to help us out and hopefully renaming the file and running SFC will solve the problem. 

Do you have that KB article with refers to this problem and the solution? This way the rest of us can benefit.


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## paj692

http://support.microsoft.com/default.aspx?scid=kb;en-us;297694
http://support.microsoft.com/default.aspx?scid=kb;en-us;308337
http://support.microsoft.com/default.aspx?scid=kb;en-us;841570
The last one has the mup.sys thingy in init. Sorry it took so long. Byee

This problem occurs with XP SP2? Anyway, trying to connect 98SE and XP is difficult at best and probably by design. (suggested fix, upgrade non-XP machine to XP)  
Also I couldn't get XP SP2 to work on my system, but my brother had no problems.
Also, I can't get any connections with my firewall down, and all the advanced options have to be checked (how safe is that?)
Any surefire fix for the connectivity problem would be appreciated. Also, anybody know how to rebuild the Administrative Tools console?
How foolproof is a reinstall in place? The microsoft technique involves putting the CD in and doing an install(upgrade). Is the install /unattend the same thing? I would get my AT console back (or I suppose I could create a new user ID and get it back that way), I just don't want to 'start over'. Thx PAJ


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## Bob Cerelli

According to that article, the causes are not of the way XP starts to ssign network shares. It was just pointing out the differences. In fact that information was only listed in the "MORE INFORMATION" section.

The cause, as listed in that article and previously mentioned in this thread is "This behavior occurs if you map a network drive to the first available drive letter after the drive letters for the local volumes and CD-ROM drives. When you install a new device or volume, Mount Manager, which assigns drive letters to volumes, does not recognize the mapped network drive and assigns the next available drive letter to the new device or volume. This causes a collision with the existing mapped network drive. "

Although the error message is the same, the cause seems a bit different from what is in that article. 

Also, where in that article does it suggest renaming "mup.sys"?


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## the_source

Hi everybody,
I have the same problem, but not with XP.
Some W2K computers access a Linux server to pickup some datas.
Since yesterday the message "Local device name already in use" appears.
I can ping the name of the server and its IP but impossible to map the drive U: as requested by the application in use.
I verified all network settings but since I can ping either the name nor the IP, I assume that these settings are correct.
Any idea on how to solve this problem on Windows 2000.


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## steveb79

Thanks for your input on this thread... but I have to say insulting people who are donating their time to try to help out a stranger is not a great way to get additional help...

Of course people are going to suggest the basics (restarting, disconnecting network drives, etc.) before they jump in and start suggesting solutions that could get a person whose technical background is unknown in trouble (destroying the admn. tools panel)

Anyway I am having a simialr problem with a basic home network setup, (pc/laptop and linksys router) I have found that if I go into network connections and disable the network connection on the pc (the machine I cannont connect to) wait about a minute and enable it, then wait 5 minutes or so, I am able to access all the network resources again from the laptop until I put the laptop in standby or hibernate then when I boot back up everything (network resources) is gone again. I am unable to ping the pc from the laptop, cannot search for a computer name etc...

Repairing the network connection from the pc does not have the same effect, it has to be disabled and enabled in the manner I noted above... *JT try that process for me and see if are dealing with a similar problem*

And to the higher level tech guys on the site... what does that repair process tell us could be going on?? I have not done a *deffinitive* test to see if restarting the machine has the same effect, but I don't think it is fixing the problem from my prior troubleshooting...

as a refresher, I can access network rescources on my *pc* from my laptop, until my *laptop* hibernates or goes into standby...then disabling and enabling my network connection on the *pc* fixes the problem until standby/hibernation on laptop again...

Hope this helps with the originaly posted question, I am getting the same "local device name in use" error message when the network connections are not working properly.


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## the_source

Concerning me, the problem have been solve.
A bad DNS entry was involved.
Thanks for your help.


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## martin.rex

I have had this problem. 

I've got a small office with a Windows 2000 Server running both the DNS (Directory Name Server) service that manages the domain, and DHCP (Dynamic Host Configuration Protocol) service that issues the IP address automatically to the workstations.

The symptom: I came in this morning after a power failure the night before. Two of the four Windows XP Pro workstations could not find the network at all. On one of these workstations, clicking on a mapped network drive (from windows explorer) would sometimes give the "Local device name already in use" message and sometimes give the "network drive can not be found" message. Rebooting did no good. I disconnected the network drives and could not reconnect because the server did not show up in the listed computers on the network.

The problem: turned out to be that the DHCP service had not recognized the workstation and had not issued an IP when I booted and logged in to the workstation. I don't know why this was the case. I discovered the problem at the server when I clicked on the DHCP service icon then Scope then Address Leases and saw only the two workstations that were connecting properly on the list of issued IP addresses. (You can also see the workstations that have been issued IPs by clicking on the DNS service icon then selecting "Forward Lookup Zones" and your domain name.)

The solution: was to disable then re-enable the network connection at the workstation. I was tipped off to this by an earlier post in this tread. At the workstation, I right-clicked the "Local Area Network connection" icon in the task bar, then selected "properties", then selected "Disable". Then did it again and selected "Enable". First, you will see a message saying that the connection is waiting to be issued an address from the server, then it will show it is connected and everything will work. You can access the internet and re-map the network drives.


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## null

I too was unable to use a network drive today, tried disconnecting it, re-mapping it but was unable to see any network folders. This was happening on only one computer, the domain controller was working fine and no network problems. I disconnected the computer from the domain hoping that it would solve the problem upon reconnecting, but was unable to log in to the domain due to the NetLogon service was not running, nor would it start manually.

To finally get everything working, try running the WinsockFix utility found here: http://www.dslreports.com/r0/download/544752~62fe0e8dc00fac87e6f0f83c54d283a4/WinsockFix.zip

Afterwards, you will need to re-enter all ip addresses so write them down beforehand since you'll need them. After a reboot, everything was back to normal.

Hope this helps someone else.


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## GadJet

Reading the posts here, I liked the idea that I needed to disconnect a mapped drive first before mapping it in order to get around the "already in use" message. After doing so, rather than mapping the host name (which didn't work, message= unable to find network), I mapped the IP address followed by the share name. It worked.


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