gomezconst1977 Said:
"could not back up I phone because not enough space. how do I find out what drive I need to make more room to back up?"
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What to Do:
See how much room you need after, and then clear space prior to backing up....
See How Much Room is Needed:
How to Check the Storage on your iPhone, iPad, and iPod touch - Apple Support
Get an external drive that is at least 1.5 times the internal storage capacity.
Clear Space:
Try clearing internal storage. Then, perform the backup though use of the following:
What Space to Clear:
A. Clear Temporary Internet Files:
Clear your Temporary Internet Files(Cookies & Cache) of Safari:
Also...
B. Clear "Other":
Clear the storages named "Other". It basically contains unnecessary files such as caches that are used for system ease of use - all of which gather over time: How to Clear "Other" in your iPhone's Storage - Use Backup - User Tips. Caches would be being used for remembrance of application use. So, clearing other may be the way to go about this, as it would be performs through use of a computer.