Microsoft-Windows-Hyper-V-VMMS/Admin, Event-ID 15268

Log NameMicrosoft-Windows-Hyper-V-VMMS/Admin
SourceHyper-V-VMMS
Event-ID15268
LevelError
UserSYSTEM
Task CategoryNone
MessageFailed to get the disk information.
Check if an *.iso-File is mounted on a virtual dvd drive (with powershell)
Get-VM | Get-VMDvdDrive | ? DVDMediaType -eq "ISO" | select VMName, ControllerType, ControllerNumber, Path

If so, unmount them and check if the error persists.