Time Machine External HDD Question

[AbsenceOfTruth]

I already have an external hard drive but the whole thing is already formated with a lot of files. Do I have to reformat it for time machine to work? I can't make any partitions, as the whole thing is formated as one partition.

Thanks!

 

[Nugget]

From 25 minutes ago, in this forum:

https://forums.macrumors.com/threads/371779/