Scheduler task - dismount blocks drive letter

[jamesdts]

Hello,

I encounter a strange problem with volume dismount.
OS : Windows Server 2008 R2 SP1 64bits
Veracrypt version : 1.17 64bits
Volume type : full partition
I'm on the Administrator account, full privileges

As I want to mount/unmount the volume and share/unshare it at the same time, I use 2 .bat scripts to do those operations.

Here are the parts regarding the veracrypt command for :

• mount :
  "C:\Program Files\VeraCrypt\VeraCrypt.exe" /q /v \Device\Harddisk1\Partition1 /l y
• dismount :
  "C:\Program Files\VeraCrypt\VeraCrypt.exe" /f /s /q /d y

Launched manually, both scripts are working very well and there is no problem.

The problem is occuring when I try to automate the dismount script with the Windows scheduler task.
The task completes "succesfully" (meaning no error) and the volume is dismounted.

But the drive letter (Y:, here) is not released. It still appears into the computer explorer, and when I try to enter it, I got an error message : "Location is not available"

If I try to execute once again the mount script, it's not working anymore and the volume isn't mounted, as if the drive letter was still used.

Note : if I try to mount the volume on another drive with another letter (Z, for example), it's working fine.

The only way I got to free this drive letter is to reboot my server...then it's working fine again, until the next automatic scheduled dismounting operation...

I tried every options into the scheduled task, change priority, privileges, nothing worked.

I repeat to clarify mo position : launched manually, everything is working fine ; launched with scheduler task, the drive letter isn't released.

By browsing this forum and others website, I find some clue about the regedit information into HKEY_LOCAL_MACHINE/SYSTEM/MountedDevices, about some keys listed here blocking the drive release.

I've checked this point, and it's not solving my problem.

Does anybody already have the same problem ?
Any idea how to solve it ?

And no, the automatic dismounting options into veracrypt don't suit to me :)

Thanks !

[JB Borden]

Did you ever find a resolution to this issue? I have EXACT prob. on VC1.19, full partition

[Alex]

Hi,

Strange. Could you try to remove the letter via diskpart?

DISKPART
REMOVE LETTER=Y

[jamesdts]

Hello,

It's not working, error message :
"Virtual disk service error :
The path is not found."

And the unavailable drive is still present into my computer explorer.

[Alex]

Check

mountvol y: /d

or

mountvol /r

For details:
https://veracrypt.codeplex.com/wikipage?title=Issues%20and%20Limitations

[Konstantinos N]

Any updates on this? I have exactly the same issue as the OP, using Win 10 1703 64bit, Veracrypt 1.21. Script using Task Scheduler to mount/dismount a file volume during user logon does not release drive letter properly. Same script works great when run outside of Task Scheduler. The exact command line being used is

"C:\Program Files\Security\VeraCrypt\Veracrypt.exe" /d y /f /s /w /q background

The script is run with 'highest privileges' in Task Scheduler.

[Simeon Steffen]

Same Problem here
using Version 1.23-Hotfix-2 on Server 2012 R2 (Build 9600)

Start Command is:
$startstring = A:\App\VeraCryptPortable.exe /s /q /d A:\Container\backup.hc
iex $startstring

no problems running this command in shell
but by starting this via tasksched, driveletter B: (the encrypted container) is sticky.

Get-WmiObject -Query "select * from Win32_LogicalDisk where name='B:'"

DeviceID : B:
DriveType : 3
ProviderName :
FreeSpace :
Size :
VolumeName :

checking with diskpart. There is no disk an no volume
tried cleandrive and diskpart
no way getting rid of B: