[MS-DOS Batch] Automatically determine if drive is already mapped

[Xtreme $niper]

I didn't know if I should start this topic under "Programming" but it seems to be the only place to put it.

I want to run a batch file that will automatically map a network drive before it continues the script. The problem I have is that if for some reason the drive is already mapped, or the batch file has been run twice in one session, the "net use" command returns an error. The script still works in the end, but I would like to bypass the "net use" command altogether if the drive is already mapped.

I've been digging through the net trying to find anything that can help me out, but to no avail. The closest thing I can find is just typing "net use" can tell you if the drive is already mapped or not, but I can't take any one piece of that result and use it in my script.

Does anyone have any suggestions? My purpose here is to write an IF statement that determines:

IF drive X: is already mapped, then skip net use command and proceed with the remainder of the script.

ELSE, run net use command and proceed with the remainder of the script.

I figured ERRORLEVEL could come in handy, but that only works after I get the error that I'm trying to avoid in the first place.

Thanks!

[Joe User]

How about using IF EXIST for a file on the mapped drive?

Asssuming W: is your mapped drive.

IF NOT EXIST W:\. netuse..etc..

[t_r_nelson]

I would be careful with what you are checking. If the user mapped a different drive than the one that is supposed to be there, it may see a drive mapped and skip the mapping.

What we have done is unmap and then map the drive in the same script. This will ensure that the correct drives are mapped to the desired letter every time.

[Joe User]

You could always look for a specific file to that share, which should eliminate the chance of having the wrong share mapped.

Unmapping the share could cause issues if other processes are using the same share.

[Xtreme $niper]

I would be careful with what you are checking. If the user mapped a different drive than the one that is supposed to be there, it may see a drive mapped and skip the mapping.

What we have done is unmap and then map the drive in the same script. This will ensure that the correct drives are mapped to the desired letter every time.

Very true. I thought about that but I realized that this is happening in a fairly controlled environment... but I suppose it would be good to do. The only downside is if I try to unmap it while another resource is using the same drive to do something, causing other errors in the process.

How about using IF EXIST for a file on the mapped drive?

Asssuming W: is your mapped drive.

IF NOT EXIST W:\. netuse..etc..

I might give that a try, thanks. I suppose maybe I can merge these two suggestions together? To unmap a drive you have to make sure the drive is mapped in the first place otherwise another error will appear. *sigh*

Also, thanks for your speedy replies.

EDIT:

You could always look for a specific file to that share, which should eliminate the chance of having the wrong share mapped.

Unmapping the share could cause issues if other processes are using the same share.

Yes exactly. If I look for a specific file on that share, I wouldn't need to unmap at all.

I'll give that a try now and report back.

[t_r_nelson]

Good point, Joe. I was just considering the case of the script running at login.

[Joe User]

I made an assumption that mappings are needed, can you run the process using UNC without having to map to a specific drive letter?

Good point, Joe. I was just considering the case of the script running at login.

I learned that the hard way, with WFW 3.11.

Multithreaded batch processing, completely crazy, but it worked.

[Xtreme $niper]

Alright I just gave this a try and it seems to work perfectly fine so far. I'll keep testing to make sure.

@echo off

echo --------------------------------------------------

echo Now running database maintenance. Please wait...

echo IMPORTANT: DO NOT TOUCH THE COMPUTER DURING THIS PROCESS

echo --------------------------------------------------

IF EXIST \\domain and filename here.exe (

echo The drive is already mapped.

GOTO SKIPPED

) ELSE (

echo The drive has not yet been mapped.

net use x: \\domain and share here Password /user:domain\user

)

:SKIPPED

[command that I need to run regardless]

echo --------------------------------------------------

echo Maintenance complete.

echo --------------------------------------------------

pause

Thanks for the help guys! I'll post here again if something comes up. The only thing I'm uncertain about is if it's okay that I don't specify X: in the EXISTS statement.

[jake1eye]

Here is a link to a HTA from the Hey Scripting Guys that uses a HTA to list available drive letters and how to map that drive.

Hey Scripting Guys

[Xtreme $niper]

Here is a link to a HTA from the Hey Scripting Guys that uses a HTA to list available drive letters and how to map that drive.

Hey Scripting Guys

Thanks, but that seems to be for VBScript. I'm just working with command line batch.

[Joe User]

Alright I just gave this a try and it seems to work perfectly fine so far. I'll keep testing to make sure.

@echo off

echo --------------------------------------------------

echo Now running database maintenance. Please wait...

echo IMPORTANT: DO NOT TOUCH THE COMPUTER DURING THIS PROCESS

echo --------------------------------------------------

IF EXIST \\domain and filename here.exe (

echo The drive is already mapped.

GOTO SKIPPED

) ELSE (

echo The drive has not yet been mapped.

net use x: \\domain and share here Password /user:domain\user

)

:SKIPPED

[command that I need to run regardless]

echo --------------------------------------------------

echo Maintenance complete.

echo --------------------------------------------------

pause

Thanks for the help guys! I'll post here again if something comes up. The only thing I'm uncertain about is if it's okay that I don't specify X: in the EXISTS statement.

IF EXIST \\domain and filename here.exe (

Once you use a UNC connection you're going to be logged into the server as the current user. If the users are different, then you're going to have a problem. You should specify the X: in the if exists.

[Xtreme $niper]

Hmm alright, so then should I do:

IF EXIST X:\\address\file.exe

or

IF EXIST X:\file.exe ?

For some reason I'm tempted to use the second one but the first one seems more technically correct to me...

[Joe User]

Hmm alright, so then should I do:

IF EXIST X:\\address\file.exe

or

IF EXIST X:\file.exe ?

For some reason I'm tempted to use the second one but the first one seems more technically correct to me...

X:\file.exe is what you want, (assuming it's in the root of the share)

[Xtreme $niper]

Alright I thought so (yes it's at the root). Thanks.

But now I have another problem. I want to schedule this using the "Schedule Task" app on WinXP. The only problem is the computers here are required to press CTRL+ALT+DEL before you can log in (secure logon). For some reason the batch script fails to do any mapping when it is run at the "press CTRL+ALT+DEL to log in" screen.

However, if I do press CTRL+ALT+DEL and go to the actual log in screen (still not logged in) the script works fine. Any ideas why, or how to get around this?

EDIT: I ran into this idea here, http://joedix.com/tech_help/2006/07/schedu...running-wo.html but I think that would be a pretty big security risk, no?

Edited January 30, 2008 by Xtreme $niper

[Joe User]

Alright I thought so (yes it's at the root). Thanks.

But now I have another problem. I want to schedule this using the "Schedule Task" app on WinXP. The only problem is the computers here are required to press CTRL+ALT+DEL before you can log in (secure logon). For some reason the batch script fails to do any mapping when it is run at the "press CTRL+ALT+DEL to log in" screen.

However, if I do press CTRL+ALT+DEL and go to the actual log in screen (still not logged in) the script works fine. Any ideas why, or how to get around this?

EDIT: I ran into this idea here, http://joedix.com/tech_help/2006/07/schedu...running-wo.html but I think that would be a pretty big security risk, no?

What account are you running the task under? Does it have a password?

[Xtreme $niper]

I'd be running this task under non-administrator accounts I believe. All accounts have to have a password, and every user has to press the CTRL+ALT+DEL combo before logging in.

I'm not sure why but it seems drive mapping doesn't work if you don't press CTRL+ALT+DEL.

EDIT: I just did another round of testing. The drive mapping actually doesn't work in ANY form if your account is locked. I previously thought as long as you hit the safe logon combo first you'd be okay, but apparently I was wrong.

As long as the system is at the login screen (even though the account itself is logged in) the application that needs to be run from the network share won't run, causing the script to fail.

Any ideas?

Edited January 31, 2008 by Xtreme $niper

[Joe User]

Ok, that's a little strange, I run batches via the task shceduler in Windows 2000 all the time.

Are you on a domain? What OS/SP are you using (XP sp2?)?

Have you tried using an admin account?

Are you using the task scheduler or the AT command?

Also, try this, get a copy of whoami.exe from the MS resource kit and pipe the output to a local file, see if it's using the correct account.

[Xtreme $niper]

Well I guess it's more complicated than just that... I forgot to mention I'm using an application called TestPlanner that automates some tasks for you by controlling the keyboard and mouse to accomplish "macro" like tasks.

The script itself actually opens and runs, but the problem is once the TestPlanner app runs, it's supposed to do a few things. One of which is to open the run window from the start menu and run another application... but for some reason the keys are never mapped to the text field within the run window and so the script fails.

So now I realize your ability to help me out can easily end here, because you probably have no idea what this TestPlanner application is...

The problem is that I am just an employee in a corporation, so there is no chance of me getting admin access. I don't think that's the problem though. I think that because the computer is in a locked state, the text field in the run command window can't be selected and so the script fails when it is trying to enter text into a field that cannot be selected. It looks like I just can't get a fix for that.

[Joe User]

Well I guess it's more complicated than just that... I forgot to mention I'm using an application called TestPlanner that automates some tasks for you by controlling the keyboard and mouse to accomplish "macro" like tasks.

The script itself actually opens and runs, but the problem is once the TestPlanner app runs, it's supposed to do a few things. One of which is to open the run window from the start menu and run another application... but for some reason the keys are never mapped to the text field within the run window and so the script fails.

So now I realize your ability to help me out can easily end here, because you probably have no idea what this TestPlanner application is...

The problem is that I am just an employee in a corporation, so there is no chance of me getting admin access. I don't think that's the problem though. I think that because the computer is in a locked state, the text field in the run command window can't be selected and so the script fails when it is trying to enter text into a field that cannot be selected. It looks like I just can't get a fix for that.

There's one last chance, you can try this, but I don't think it will work, see if the TestPlanner has the ability to 'allow service to interact with desktop'. In windows 2000, you could set this in the services control panel.

Honestly, I don't think that would solve your problem though. Since it's a macro program it most likely needs an unlocked console to work.

[Xtreme $niper]

There's one last chance, you can try this, but I don't think it will work, see if the TestPlanner has the ability to 'allow service to interact with desktop'. In windows 2000, you could set this in the services control panel.

Honestly, I don't think that would solve your problem though. Since it's a macro program it most likely needs an unlocked console to work.

I just took a look at the program, and I unfortunately have found no such feature. Thanks for the suggestion though.

The funny thing is that although it can't select a text field to enter text into as part of the macro, it still successfully opens the Run command window via the "Windows key + R" shortcut.