Cannot connect to the Citrix XenApp server. SSL Error 61

Users start to get error " Cannot connect to the Citrix XenApp server. SSL Error 61: You have not chosen to trust the SSL certificate"

Cause:  SSL certificate has been renewed in Access Gateway or any upgrade happened in Access Gateway / Netscaler version

Solution:

1.) Upgrading the Citrix Receiver to Latest version (4.2.0.10) may fix the issue
2.) In some cases clearing the Temporary Internet Files may also be needed.