Xenserver dead VDIs after upgrade 5.0 to 5.5

Struggled with some dead VDIs on one of my xenserver after upgrade to 5.5. The virtual disks got duplicated, can't remember directly but i think the cause are snapshots. I've tryed some really deep things in the xenstore to get things sorted out but none helped. As the VMs were full productive and i dont wanted to get in the risk of a emergency desaster recovery, i ended up exporting full backups of the vms, cleaned the storage completly and imported them again. Not really amazing fix but at least one problem less.

Here you can view the thread on the support forum: