Fix ‘Dirty Environment Found’ message while installing Cisco AnyConnect with MDT

I was recently troubleshooting our MDT task sequence to try to find the cause of a ‘Dirty Environment Found’ message appearing while deploying computers.

I traced it down to the Cisco AnyConnect installer, but it took a lot of googling and trial and error to find a way to fix it.

The cause

It turns out that the ‘Dirty Environment Found’ message was appearing because the AnyConnect installer was detecting that Explorer wasn’t running and trying to launch it, which re-ran the RunOnce commands and in turn relaunched Lite Touch. The installer also seemed to stall for a while, so it was taking approximately 15 minutes to install instead of 15-30 seconds.

The solution

One possible solution would be to set HideShell=NO so that explorer is running during deployment. We have our MDT rules configured with HideShell=YES so students can’t interfere with the computers while they are deploying, so this isn’t an option for us.

The method that I found which fixes this was to temporarily replace the RunOne registry key with an empty one so that they don’t execute while AnyConnect is installing.

I added the following lines to my AnyConnect install script:

# Move the RunOnce key so that AnyConnect will install sloothly
Rename-Item HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce RunOnce.bak
New-Item HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce

#########################################
# Place code to install AnyConnect here #
#########################################

# Put the RunOnce key back so we don't break MDT
Remove-Item -path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce -force
Rename-Item HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce.bak RunOnce

This is unfortunately a bit of a hack, but until Cisco fix up their installer it’s one i’ll live with as it does speed up deployments by 15 minutes.