This article is intended for Citrix administrators and technical teams only.Non-admin users must contact their company’s Help Desk/IT support team and can refer to CTX297149 for more information

-Performance is affected by wfica32.exe as it uses high amounts of CPU during ICA connections.

-High CPU usage for process wfica32.exe when users are double hopping (Opening a Citrix ICA Session while already on a Citrix ICA Session)
Performance is highly impacted 

No side effect has been reported up till now.

Allow the SlowHPCPolling registry key to specify polling rates from 2 - 500 ms.

When installing Receiver for Windows on an XenApp (server) VDA, the SlowHPCPolling registry value is initially not present. That implies its value will be 2 (as 2 ms). 
This mean Receiver (wfica32.exe) will be polling certain libraries and drivers every 2 milliseconds.

The value can be increased up to 500 ms. There is no ideal value as same value yields different outcomes in different environments. 
It is therefore important to test in each environment in order to find that environment's ideal value. The balance is between higher performance with higher CPU usage (2 ms) and lower performance with lower CPU usage (500 ms).

Registry setting:
                        For 32 bit machines, locate the following registry key: 
                        HKLM\SOFTWARE\Citrix\ICA Client\Engine\Configuration\Advanced\Modules\WFClient

                        For 64 bit machines, locate the following registry key:
                        HKLM\SOFTWARE\Wow6432Node\Citrix\ICA Client\Engine\Configuration\Advanced\Modules\WFClient

                        Create or modify the following value:

                        Value:SlowHPCPolling
                        Type: REG_SZ
                        Range: 2-500

Problem Cause