Slow Application Authentication, Enumeration, and Application Launch with Citrix Receiver for Apple IOS Devices
Symptoms
When using an iOS device such as iPhone, iPad, you might experience one of the following issues when connecting to your XenApp Services site in a XenServer environment:
- The iOS device intermittently fails to make a connection to the XenApp Services Site. (times out).
- When attempting to connect to the XenApp Services Site, the authentication and enumeration process would take an excessive amount of time to complete.
- When the Authentication process has completed and the published applications are enumerated, not all the applications that the user has access to are displayed.
- When attempting to start an application from your Services Site, you might receive Protocol Driver Error.
Cause
The problem is caused by the XenServer PV Ethernet Adaptor Advanced Offload Properties.
When you install the XenServer virtualization drivers, the network interface has the following four Offload adaptor settings:
- Large Send Offload
- Offload IP Checksum
- Offload TCP Checksum
- Offload UDP Checksum
Resolution
As a workaround, you can just Disable all the four properties. No restart is required.
Make these changes on your XenApp, Citrix Secure Gateway, and Web Interface servers. Once these changes are made, you should be able to connect with your iOS devices quickly and without any issue.
Status
This workaround applies to Windows Server 2003 and 2008. This issue does not affect Windows Server 2008 R2.