Hyper-V 2012 R2, integration services issue on multiple VMs

Hello,

I came to you because we encounter a technical issue on one of our Hyper-V (2012 R2).

Our backup (Veeam backup in last version) are still failing with error :

Guest processing skipped (check guest OS VSS state and integration components version)

After checking integration service states of those VMs on the Hyper-V, we get this result :

Get-VM | ft Name, IntegrationServicesVersion

Name                                                        IntegrationServicesVersion
----                                                        --------------------------
xxx-3REP-01                                                 6.3.9600.16384
xxx-ADMIN02
xxx-BAK02                                                   6.3.9600.16384
xxx-MAIL-01
xxx-SCOM-01-1                                               6.3.9600.16384
xxx-SQL02                                                   6.3.9600.16384
xxx-VC-01                                                   6.3.9600.16384
xxx-VD01
xxx-VMM02
xxx-VMM03
xxx-WEB01


Get-VMIntegrationService xxx-vmm02 | Select Name,OperationalStatus

Name                                                        OperationalStatus
----                                                        -----------------
Time Synchronization                                        {Ok}
Heartbeat                                                           {Ok, Ok}
Key-Value Pair Exchange                                  {LostCommunication}
Shutdown                                                           {LostCommunication}
VSS                                                                     {LostCommunication}
Guest Service Interface                                     {LostCommunication}

I already try to disable, then enable the operationalStatus :

Disable-VMIntegrationService -VMName MyVM -Name VSS,Shutdown,"Key-Value Pair Exchange"

Enable-VMIntegrationService -VMName MyVM -Name VSS,Shutdown,"Key-Value Pair Exchange"

The status is OK, but If I retry my backup I have the same error.

So, is there a way to reinstall integration service component without rebooting ?