Insufficient Space for Time Machine

jonathanmoskovitz wrote:

My 2TB Seagate external hard drive is saying it does not have sufficient space to back up my Macbook Pro (2TB, but only 855gb used). I have ~400gb of other files on my external hard drive, so maybe that is causing an issue, though I have had other non-partitioned files on the external drive for a while and I never had a problem. My external drive is only able to store one backup at this point and can't create any new ones.

Any ideas on how to fix?

It is known TM likes to have it's own dedicated drive.

You can try erase/reformat/initialize the drive as new and start a new TM backup if you want to proceed with that drive.

Erase and reformat a storage device in Disk Utility on Mac

Erase and reformat a storage device in Disk Utility on Mac - Apple Support

If you value your user data

3-2-1 Backup Strategy: three copies of your data, two different methods, and one offsite.

More than one device, more than one backup methodology.