Error message xceed archiver error

Backup all of a sudden receiving this error:

7/12/2022 12:55:13 PM [Error] Failed to backup “GoldMine” folder in “C:\ProgramData\GoldMine”. Xceed archiver error. > The file item could not be opened for reading.
Type: Xceed.FileSystem.DiskFile
FullName: C:\ProgramData\GoldMine\flags.bin > The process cannot access the file ‘C:\ProgramData\GoldMine\flags.bin’ because it is being used by another process.

Possibly GM needs to be closed but never saw that before.

Hi Fred_Roven,

To resolve the issue, please try to use 7zip as your Archive format.

Thank you and sorry for the inconvenience.