Repair Disk Problem

While cleaning up present Intel IMac on IOS 13.10 and preparing to migrate to IMac M3 there was a problem with current TimeMachine backup disk. When the Mac restarted the backup external drive was not available. Opened Disk Utilities and there was a message concerning the disk about unable to complete backup in progress due disk problem. So I tried to run First Aid on the disk to repair. It ran for hours without completing. I saw another thread on this issue and the concern was Forcing Disk Utility to Quit. There was no additional information I saw that provided a resolution. So I decided to Force Quit and restart in safe mode to see if the issue could be resolved. Once in safe mode I was able to access the disk utility to repair again. This ran all night without resolution. Got to a point in the details Checking Multi link files. I decided to Restart the machine. After the restart all was well and TimeMachine Disk was mounted and an auto backup was completed. SO HAPPY! So just wanted to put this out for knowledge.