error message, time machine cannot be reliably restored, erase backup history and start a new back up, is this safe

Error Message appears.......something is wrong

Time Machine cannot be reliably restored......this is what is wrong

Erase backup history.......no reason to keep the history if it cannot be used to reliably restore the Mac

Is this safe?.......a lot safer than doing nothing. With new backups, you at least have a chance to use them to restore your Mac reliably if/when the time comes.

If you don't want to lose the old backups.......even though they cannot be used to reliably restore the Mac......use the Archive function in AirPout Utility to copy all of the data on the Time Capsule hard drive over to a USB drive connected to the USB port on the Time Capsule.......before......you erase the Time Capsule hard drive.

The USB drive will need to be at least as large as the Time Capsule hard drive and must be formatted n Mac OS Extended (Journaled) before you can use the Archive function in AirPort Utility.