XS 7.1 - CIFS ISO virtual disk could not be found

I have had two separate XS 7.1 patched thru HF 14 that has issues loading ISO's to a VM. Usually one host server will work while the others will throw this error - "This operation cannot be performed because the specified virtual disk could not be found". Usually detaching the CIFS ISO Library and re-attaching will allow it to work for a couple time before it stops and throws this error again. Attached is the smlog when trying to load the ISO.