I had the same issue while testing a package (I terminated the PS process then re-ran the App Deploy script) and had five different blocked applications that the scheduled task could not remove for whatever reason. I ended up writing the script below to remove the registry values, just in case it ever happened again.
Get-ChildItem "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options" -Recurse |
ForEach-Object { Get-ItemProperty $_.pspath } |
Where-Object {$_.Debugger -like "*ShowBlockedAppDialog*"} |
Remove-ItemProperty -Name Debugger
On a side note, thanks for putting this Toolkit together, it is very helpful and time-saving :)