Issue:

Not able to provision any new VDIs to existing machine catalog. All the existing machines work fine.

Solution:

1. As per https://support.citrix.com/article/CTX213019, enabled enableHttpDataStoreAccess value on vcenter but it didnt help.
2. Thought to create new cluster in vcenter and move some hosts to it and add it to xendesktop, and publish new VDIs to it.
   • As a part of this process, created new cluster, moved some hosts to it.
   • One of the hosts in earlier old cluster was moved to maintenance mode because it was not moving all the VMs from it.
   • so finally one host was in MM and two hosts were removed from cluster. Issue resolved. Not sure which host caused the problem, but removing hosts resolved the issue.