VDP Unable to Deploy VDP 6

Hi All,

We use port 81 for vCenter as an alternative HTTP port however when im trying to deploy the VDP appliance i get the following error

Unable to verify vCenter listening on specified HTTP Port.  Please re-check values and try again

Ive double checked and vcenter is listening on this port all other credentials are correct as ive deployed version 5.8 sucsessfully last week using the same credentials. Ive also checked the host file on the backup appliance and this shows the correct ip's anyone else getting the same?? Or have any idea what i can double check next?

Thanks

Alex