How to Disable the Microsoft Language Bar Agent (Red Pen) in the System Tray on a Citrix Server

Easy Fix:
Regsvr32.exe /u msutb.dll
regsvr32.exe /u msctf.dll
Click OK



Official Citrix Fix (not had much luck with this one)
This solution applies only to Citrix PS 4.5 and higher

Seamless Global Registry Flags

These values affect all Seamless connections to a server.

To configure a Global Seamless Flag, create the value SeamlessFlags, and then specify a Value corresponding to one or more of the choices listed below:

Registry Key: HKEY_LOCAL_MACHINE/System/CurrentControlSet/Control/Citrix/wfshell/TWI
Value Name: SeamlessFlags
Value Type: REG_DWORD
Values: Flags 1 through 19 below

If more than one of these flags is needed at the same time, add them together as in the following examples:

Note: All values are in Hex format.

Example 1: To use Flags 1 and 8 below, the Hex value for SeamlessFlags would be 0x1 + 0x200 = 0x201.
Example 2: To use Flags 1, 8, and 9 below, the Hex value for SeamlessFlags would be 0x1+0x200+0x400 = 0x601.
Example 3: To use Flags 5 and 6 below, the Hex value for SeamlessFlags would be 0x20 + 0x80 = 0xA0.

IF a SeemlessFlag already exist, you will need to add this value to the current existing value.

The value to disable the language bar agent is: 0x40000

If the current value is 0x1 then 40000 + 1, the nex value should be 40001 to keep the current setting and disable the language bar agent.

full Citrix article CTX101644