XenCenter has a simple and intuitive UI. However when problems happen, the log tab sometimes doesn’t contain enough information to help with debugging the issues.  I found it very useful to take a look at the debug log in %appdata%\Citrix\XenCenter\logs\XenCenter.log.  For example, the log file may be in C:\Documents and Settings\<user name>\Application Data\Citrix\XenCenter\logs directory. Please note that Application Data directory may be hidden.

Here is an example of what’s contained in the log:

… 

2008-06-10 10:02:05,579 INFO  Audit [Main program thread] – Operation started: ImportVmAction: pdxen2: Pool 95e79feb-a2fd-f744-8f03-a47ce57a2d2e (): Host 817c97de-2b6d-4670-a00d-0dcccff42531 (pdxen2): Preparing to Import VM
2008-06-10 10:02:06,016 DEBUG XenAdmin.Actions.ImportVmAction [7428] – Importing Rio-style XVA from C:\XenVm\Auto-Win2K3-R2-SP2-32bit-TS-IIS-.NET-SysPrep.xva to SR 10.2.248.123_local
2008-06-10 10:02:06,016 DEBUG XenAdmin.Actions.ImportVmAction [7428] – SR is not shared -- redirecting to 10.2.248.123
2008-06-10 10:02:06,016 DEBUG XenAdmin.Actions.ImportVmAction [7428] – Using https://10.2.248.123:443/import?session_id=OpaqueRef%3A4769e023-7c64-ca54-f6e0-e257b8be522f&sr_id=OpaqueRef%3A2fc1e3d8-0763-0099-7151-98f4610f37b1 for import
2008-06-10 10:02:06,063 DEBUG XenAdmin.Network.HTTP [7428] – HTTP PUTTING file from C:\XenVm\Auto-Win2K3-R2-SP2-32bit-TS-IIS-.NET-SysPrep.xva to https://10.2.248.123/import?session_id=OpaqueRef:4769e023-7c64-ca54-f6e0-e257b8be522f&sr_id=OpaqueRef:2fc1e3d8-0763-0099-7151-98f4610f37b1&task_id=OpaqueRef:1160c6fb-4a03-39c4-3336-0973573958c2
2008-06-10 10:02:25,469 DEBUG XenAdmin.Actions.AsyncAction [Main program thread] – AsyncAction.Cancel() was called. Attempting to cancel action