When running Citrix Corporation’s ICA Client version 10.200 and later on Windows XP on any service pack, a user logon does not load the cached profile but creates a new one instead. This caused Windows to create a temporary profile for the user’s logon session. Applications store user settings in the registry hive by calling registry functions that refer to the HKEY_CURRENT_USER (HKCU) root key, revealed. In this case, the fact that stood out was that all the systems on which the problem had occurred had recently been upgraded to a new version of Citrix Corporation's ICA client, a remote desktop application. Microsoft contacted Citrix support to see if they knew of any issues with the new client. They didn’t, but said they would investigate. Citrix published the workarounds in this Citrix Knowledge Base article and Microsoft in this Microsoft Knowledge Base article.