Time Machine Says I need 4Tb to Backup 1Tb
Time machine didn't delete old backups when disk became full like it was supposed to. So I had to erase the external 2Tb drive, after deleting all the files manually I use, to backup my 1Tb HDD in my 2013 iMac. I then reformated it with journal as usual and ended up with a clean 2tb Apple ready drive.
All is OK according to disk utility. I've unmounted/remounted, unplugged iMac and powered up from scratch but when I try and do a Time Machine backup it says I need 4.2 Tb. I only have that 1Tb HDD in my iMac. I have a few external USB drives but they don't appear on the list to not backup and they were never backed up before. Also they total more than 4.2 Tb.
So what is causing Time Machine to ask for 4.2TB ? I assume this would be the first full backup it does and then incremental. I use Time Machine now and then to recover lost files and apps so its important. But this is frustrating. Any help appreciated
iMac Line (2012 and Later)