Hyper V Back up Failed

Hello, I am now getting the following errors when i am trying to back up a Hyper V server on Symantec Backup Exec 15

Job ended: Friday, January 04, 2019 at 5:06:39 AM
Completed status: Failed
Final error: 0xe000ff18 - A communications failure has occurred with a Virtual Machine resource.
Final error category: Resource Errors
For additional information regarding this error refer to link V-79-57344-65304

Backup- VRTSRV::\\smhg-hv01\Hyper-V?Virtual?Machine\SMHG-FILE1V-79-57344-65304 - The Virtual Machine resource is not responding. Backup set canceled

Backup- smhg-hv01V-79-40960-38525 - The faster processing method for incremental backups was selected for Hyper-V virtual machine 'SMHG-FILE1'. However, that method could not be performed because either Backup Exec did not perform the previous backup or because that virtual machine is backed up with more than one backup job. Because the option 'Use the full backup method for virtual machines that do not support incremental or differential backups' was selected for this job, a full backup ran instead of an incremental backup.

Backup- VRTSRV::\\smhg-hv01\Hyper-V?Virtual?Machine\SMHG-FILE1V-79-57344-38732 - Virtual machine 'SMHG-FILE1' does not meet the requirements necessary for Backup Exec to restore individual application items. You cannot perform GRT-enabled restores of application data from this backup.

V-79-40960-38528 - The Hyper-V subsystem has reported that the Hyper-V Integration Services (HIS) inside the virtual machine do not match the version expected by the Hyper-V host.  An offline backup of this virtual machine has been performed, update the Hyper-V Integration Services to ensure online backups can be performed whenever possible.

How can i fix this?

Thanks.