Problem
In a terminal server 2012R2 environment using Autoconnect with shared network printers via MAP a number of problems occur which are most likely connected to the same issue. These all have in common, that there are inconsistent printer object lists in “Devices and Printers”, “Printers” and API-“enumprinters”.
Printer are also shown as …
- “not available” in ThinPrint Self Service
- multiple printers having the same name (network printer shares as well as local printers),
- default printer cannot be set (any error),
- default printer is shown but not really existing when you want to select it from the application when printing,
- printers cannot be deleted from old printer view but from Devices&Printers,
- printers is shown in Devices&Printers as “unknown device”,
- printers are just not there.
Cause
This phenomenon is known as ‘Ghost Printer’. The problem is created by Windows related processes. Our assumption is that the print spooler service is not working correctly and this has also been confirmed in our tests. This is a huge issue for us because we depend on the Windows API (application programming interface) and rely on the given data which are unfortunately incorrect. So, if we ask via API for a list of connected printer shares it might only return a few of them causing unnecessary printer creation attempts.
Solution
1. The first recommendation we have is to install the latest MS Update KBs.
2. The second recommendation we have is cleaning up the registry and check if this improves the situation. [Clean Up Process]
3. The following steps may also be considered.
- Make sure at least ThinPrint Engine 11.2 is installed (Product Version 11.2.593)
- Update to the new AutoConnect Version
- Activate the part of the workaround that’s been already implemented.
- Run the clean-up steps to remove affected printers.
See the description for every stage below.
Activate Workaround
The following work-flow should be considered to make sure the system is cleaned-up in first place.
- Set new registry values..
- Run the manual clean-up steps again (see bottom) and make sure no user session exists.
[HKEY_LOCAL_MACHINE\SOFTWARE\ThinPrint\TPAutoConnect]
WaitSessionReadyRetryCount (DWORD) 10 (dec)
WaitSessionReadyTimeout (DWORD) 500 (dec)
TPAutoConnect service needs to be restarted.
Via Powershell
| $RegPath = “HKLM:\SOFTWARE\ThinPrint\TPAutoConnect” Set-ItemProperty -path $RegPath -name “WaitSessionReadyTimeout” -Value 500 Set-ItemProperty -path $RegPath -name “WaitSessionReadyRetryCount” -Value 10 Restart-Service tpautoconnsvc |
Clean Up Process
This also includes a Windows related policy and registry setting that’s known to influence the behavior as well.
1. On the Terminal Servers set the computer policy “Always render print jobs on the server” to -enabled-
Policy Path: Computer Configuration -> Policies -> Administrative Templates -> Printers
2. Create the registry value “RemovePrintersAtLogoff” (DWORD) and set it to “0”.
Registry Path: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Providers\Client Side Rendering Print Provider]
Create value via Powershell
| $RegPath = “HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Providers\Client Side Rendering Print Provider” New-ItemProperty -path $RegPath -name “RemovePrintersAtLogoff” -PropertyType DWORD -Value 0 -force | Out-Null |
3. Delete all Client-Side-Rendering (CSR) sub keys on the Terminal Servers under:
Registry Path: [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Providers\Client Side Rendering Print Provider]
Delete Content via Powershell
| $RegPath = “HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Providers\Client Side Rendering Print Provider” (Get-ChildItem $RegPath).PsPath | Remove-Item -Recurse |
4. Restart the server.