I have similar issue with veeam 7. When i upgrade to ESXi 5.5 u3 build 3248547 all my backup's fail with error
Processing 'XXX' Error: Client error: NFC storage connection is unavailable. Storage: [stg:datastore-5162,nfchost:host-121,conn:vcenter]. Storage display name: [v3700_2 RAID 5].
Failed to create NFC download stream. NFC path: [nfc://conn:vcenter,nfchost:host-121,stg:datastore-5162@PXXXXX.vmx].
I try add all ESXi to host file of Veeam backup Sever but it doesn't work