Licensing
Most problems are related to Citrix and Microsoft licensing issues. First, verify that the server is running in Application Server mode not Remote Administration. Second, check that the Terminal services licensing server is running and that licenses are activated. Third, check the Citrix licensing server that the correct amount of licenses are installed. Fourth, establish a Remote Desktop Connection using both an administrator account and a regular domain users account.

No Terminal Server Licenses when attempting RDP to server from client workstation:
Delete HKLM\software\microsoft\mslicensing\store\license000 registry key

IMA Service
Verify the IMA service is started and running in Services. Check that the service is live by doing a telnet on port 1494. For example: telnet 127.0.0.1 1494
If the service is answering, you will see ICA♥ repeat continuously.

Firewall
TCP port 1494 needs to be open for external users to connect using the standard Citrix client. Though not necessary, having TCP port 3389 open for Terminal services may help to isolate problems in the trouble shooting process. Additionally, to support session reliability with Presentation Server 4.0 or later, TCP port 2598 should be open.

Create Web Interface not an option
If when running Access Suite Console for Presentation Server 4.0 and the option to Create a web interface is not present, the most likely cause is that Microsoft .NET Framework 2.0 is installed. The resolution is either to un-install .NET Framework or to add the following file in C:\Windows\System32\
mmc.exe.config
<?xml version ="1.0"?>
<configuration>
  <startup>
    <requiredRuntime version="v1.1.4322"/>
    <supportedRuntime version="v1.1.4322"/>
  </startup>
</configuration>
Remove this file if upgrading to Citrix 4.5 Access Management Console

Changing XML service port
How to change the XML service port used by Citrix Presentation Server:
1. Go to a command prompt
2. Type ctxxmlss /u and press ENTER (this will unregister the XML service)
3. Stop the Citrix XML Service in the Services in Windows Services
4. Type ctxxmlss /rnnn and press ENTER (for example to change the port to 8080 type ctxxmlss /r8080)
5. Refresh services and start the Citrix XML Service in the Services in Windows Services
6. Type telnet localhost 8080 and press ENTER twice (instead of 8080 use the port # specified in step 3)
    HTTP/1.1 400 Bad request
    Server: Citrix Web PN Server
    Date: Tue, 16 Oct 2005 14:02:41 GMT
    Connection: Close
    Connection to host lost.

Web Interface unable to login
The supplied credentials could not be validated. Either they are incorrect, or there is a problem with the authentication system. Try again, or contact your help desk or system administrator for help.
1. Type telnet localhost 80 and press ENTER twice (instead of 80 use the XML service port number)
If output similar to the following appears, then the XML service is running correctly:
    HTTP/1.1 400 Bad request
    Server: Citrix Web PN Server
    Date: Tue, 16 Oct 2005 14:02:41 GMT
    Connection: Close
    Connection to host lost.
Otherwise, consider changing the XML service port for the Presentation Server and reconfigure the XML port in the Manage Server Farms module of the Web Interface configuration management console.

Secure Ticket Authority
How to verify the Citrix secure ticket authority (STA) is running correctly:
Enter the following into a web browser running on the Presentation Server
http://localhost:port/ctxsta.dll or http://localhost:port/scripts/ctxsta.dll
http://localhost:8080/ctxsta.dll (this example is if the XML service is running on port 8080)
If the test is successful, the output will be a blank screen or say Error 405 - resource not allowed.
If the test fails, then the output will most likely be a 404 Error (The page cannot be displayed)

Web Interface Client Download
How to add a link to Web Interface 4.5.1 or higher to download a Citrix client from the local webserver:
Edit WebInterface.conf on Web Interface server:
Generally: C:\Inetpub\wwwroot\Citrix\AccessPlatform\conf or C:\Inetpub\wwwroot\Citrix\XenApp\conf
    Edit Win32Client=Default
    Ver 4.x: Win32Client=Citrix Windows Client Download&/Citrix/AccessPlatForm/Clients/ica32web.msi
    Copy ica32web.msi to C:\Inetpub\wwwroot\Citrix\AccessPlatform\Clients\
    If running Web Interface 4.x and a Citrix client is not detected, the main page will display the
    download link.

    Edit Win32Client=Default
    Ver 4.x: Win32Client=Citrix Windows Client Download&http://citrixnerds.com/clients/OnlinePlugin.exe
    # This will download version 12 client from Citrix Nerds website

    Ver 5.x: Win32Client=Citrix Windows Client Download&/Citrix/XenApp/Clients/XenAppWeb.msi
    Copy XenAppWeb.msi to C:\Inetpub\wwwroot\Citrix\XenApp\Clients\
    *Files are located in the \clients\ica32\ folder on the Citrix Components CD
    For Web Interface 5.x a redirect to a download page will occur.

    XenApp 6: Edit C:\Inetpub\wwwroot\Citrix\XenApp\conf\WebInterface.conf
    # ClientDefaultURL=http://www.citrix.com/download - Unremark this line and add correct URL
    ClientDefaultURL=https://citrix.mycompany.com/common_clients

    Copy Citrix Receiver and Plug-ins from installation media to C:\Program Files (x86)\Citrix\
    Web Interface\5.3.0\Clients\

    # ClientIcaMac=Filename:Citrix online plug-in (web).dmg,Directory:Mac,Mui:Yes
    # ClientIcaWin32=Filename:CitrixOnlinePluginWeb.exe,Directory:Windows,Mui:Yes,ClassID:
        238f6f83-b8b4-11cf-8771-00a024541ee3
    # ClientStreamingWin32=Filename:CitrixOfflinePlugin.exe,Directory:Windows,Mui:Yes,ClassID:
        4384F3C5-4A9E-4E81-9AAE-4251C2813861
    If filenames need to be modified, then edit the above lines for MAC and Windows
    Online/Offline clients

Program Neighborhood Agent
How to verify the Citrix Program Neighborhood Agent is running correctly:
Enter the following into a web browser running on the Presentation Server
http://localhost/Citrix/PNAgent/config.xml
If output similar to the following appears, then the PNAgent is running correctly:
  <?xml version="1.0" encoding="UTF-8" ?>
  <!DOCTYPE PNAgent_Configuration (View Source for full doctype...)>
- <PNAgent_Configuration xmlns:xsi="http://www.w3.org/2000/10/XMLSchema-instance">

How to securely access PNagent from the Internet using SSL:
In the \inetpub\wwwroot\Citrix\PNAgent\conf folder edit the WebInterface.conf file
AlternateAddress=On

Citrix Web Interface 5.x compatibility with legacy editions of Presentation Server or MetaframeXP
Edit webinterface.conf changing RequireLaunchReference=on to off
For Xenapp : c:\intetpub\wwwroot\citrix\xenapp\conf
For PNAgent : c:\inetpub\wwwroot\citrix\pnagent\conf

Force Uninstall Citrix Presentation Server
If the Citrix IMA service is not started and you want to uninstall Citrix do the following:
1. Go to a command prompt and change to the installation files directory on the installation media or CD
2. cd\Citrix Presentation Server
3. Type msiexec /x mps.msi CTX_MF_FORCE_SUBSYSTEM_UNINSTALL=Yes and press ENTER

Only administrators have permission to add, remove, or configure server software during a terminal services remote session
Add the following registry key:
Key: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Installer
Name: EnableAdminTSRemote
Type: DWORD
Value: 1

Disable server icons and notifications from showing in systray of user workstation
Add the following registry key:
Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Citrix\wfshell\TWI
Name: SeamlessFlags
Type: REG_DWORD
Value: 20 (hex)

Please provide a valid server installation type on the command line when executing the MSI or use Autorun to execute the installation instead
In XenApp for Windows 2008, there is no longer a default installation type
Set the CTX_MF_SERVER_TYPE property regardless of what type of installation you are performing
Example: msiexec.exe /i mps.msi CTX_MF_SERVER_TYPE="P"
P = Platinum, E = Enterprise, A = Advanced

Thin Client Intermittent Connection Dropping - Checksum Offloading
If you experience intermittent communication failure between Thin Client devices and Windows 2003 Server Terminal Services (RDP) and/or Citrix (ICA):
1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following registry subkey:
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
3. In the right pane, make sure that the DisableTaskOffload registry entry exists. If this entry does not exist, follow these steps to add the entry:
      a. On the Edit menu, point to New, and then click DWORD Value.
      b. Type DisableTaskOffload, and then press ENTER.
4. Click DisableTaskOffload.
5. On the Edit menu, click Modify.
6. Type 1 in the Value data box, and then press ENTER.
7. Exit Registry Editor.
Ref: Microsoft KB904946
* This problem may occur with certain Dell Servers specifically designed for virtualization that come with Citrix XenTools pre-installed

When launching the Citrix Delivery Services Console after installing XenApp 5.0 or Presentation Server 4.5 on Windows Server 2003, the XenApp node is missing. The administrator is unable to configure the farm.
From a command prompt, enter the following:
CD C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727 and run the following line
regasm /codebase "C:\Program Files\Common Files\Citrix\Presentation Server - Administration Snap-in\PSE.Core.dll"

The server was unable to allocate from the system nonpaged pool because the pool was empty
Windows 2003 Server Enterprise 32bit running more than 4GB RAM. Collecting pooltag data using Pool Monitor indicates a large amount of non-paged pool memory in the ICA Pool tag. If servers are rebooted on daily basis this issue has a lesser likelihood of occurring.
Citrix CTX230540 post R06 hotfix PSE450R06W2K3035 - January 12, 2011 addresses this issue.

Best Practices Printer Policy
1. Start the Citrix Presentation Server Console
2. Right click on Policies, click create policy, enter a policy name and click OK
3. Right click on the Policy name and select properties
4. Expand the Printing folder and the Client Printers folder
5. Select Auto-Creation - Check Enabled and select Auto-Create all client printers
6. Expand the Drivers folder
7. Select Native Printer Driver auto-install - Check Enabled and select Do not automatically install drivers
8. Select Universal driver - Check Enabled and select Use universal driver only if requested driver is unavailable
9. Click Apply and OK
10. Right click on the Policy name and select Apply this policy to
11. Select Servers and check the Filter based on servers to apply the policy to all servers and click OK


Migrating SQL databases
If during the initial Citrix installation the default database was selected and you want to change it from Master to something else, here are the steps that should be taken:
SQL Server:
Create a Citrix database called CTX, create a SQL user called citrix and grant the user dbo database access.

First Citrix Server:
1. From a command prompt cd\program files\citrix\independent management architecture
2. copy mf20.dsn mast.dsn
      Contents of mast.dsn:
      [ODBC]
      DRIVER=SQL Server
      UID=sa
      DATABASE=master
      WSID=CTXSERVERNAME
      APP=Citrix IMA
      SERVER=SQLSERVERNAME
      Description=Citrix
This assumes the sa SQL account was used to connect to the database. If DATABASE isn't a part of this configuration then Citrix knows to default to master.
WSID=Name of the server
SERVER=Name of SQL server

3. edit mf20.dsn
      Contents of mf20.dsn:
      [ODBC]
      DRIVER=SQL Server
      UID=citrix
      DATABASE=ctx
      WSID=CTXSERVERNAME
      APP=Citrix IMA
      SERVER=SQLSERVERNAME
      Description=Citrix

4. dsmaint config /user:sa /pwd:sapassword /dsn:"c:\program files\citrix\independent management architecture\mast.dsn"
If the datastore is using an Access database with the default settings use the following credentials:
/user:citrix /pwd:citrix (omitting these will use the defaults)
This tells Citrix what DSN to use. For this example we're telling it to temporarily use the MAST.dsn

5. dsmaint migrate /srcdsn:"%ProgramFiles%\Citrix\Independent Management Architecture\MAST.dsn" /srcuser:sa /srcpwd:sapassword /dstdsn:"%ProgramFiles%\Citrix\Independent Management Architecture\MF20.DSN" /dstuser:citrix /dstpwd:citrixpassword

This copies the necessary tables from the source DSN to the destination DSN. The MAST.dsn looks at the master database in SQL and the MF20.dsn goes to the CTX database.

6. dsmaint config /user:citrix /pwd:citrixpassword /dsn:"c:\program files\citrix\independent management architecture\mf20.dsn"

This tells Citrix what DSN to use. For this example we're telling it to use the MF20.dsn which will be used for production.

7. Stop IMA service
8. dsmaint recreatelhc
Flushes all the local host cache info out and pulls in a fresh copy from SQL
9. Start IMA service

Other Citrix Servers:
1. Copy the MF20.dsn from the first server to other servers and edit the WSID so that it's the same as the server name
2. dsmaint config /user:citrix /pwd:citrixpassword /dsn:"c:\program files\citrix\independent management architecture\mf20.dsn"
3. Stop IMA service
4. dsmaint recreatelhc
5. Start IMA service

Master Database Cleanup:
This is so it's not used accidentally
rename keytable _keytable
rename indextable _indextable
rename deletetracker _deletetracker
rename datatable _datatable

To test that everything worked properly, published a test application like Freecell using the Citrix Management Console and launch it from servers in the farm and if installed from the web interface. To make 100% sure everything works, reboot the servers and confirm no errors are in the event logs.