Back up not working (USB-C drive not recognized)

zero12

I have a Samsung 256g thumb drive. Formatted to exFat. Plugged in.

I start with Settings -->Back up location--> Reads: "USB Flash drive needs to be plugged in"

Please help troubleshoot - thank you!

de0u

zero12 I have a Samsung 256g thumb drive. Formatted to exFat.

Is the disk partitioning MBR or GUID? I have had better luck with MBR.

zero12 I start with Settings -->Back up location--> Reads: "USB Flash drive needs to be plugged in"

Does the Files app see the thumb drive?

zero12

de0u

Its mac os >> Disk Utility >> Partitioning option is greyed out.

Answer:
File app on phone does not see drive.

Tried:
Reformatted to Fat32 plugged into phone >> Not recognized

de0u

zero12 Does plugging anything into the phone's USB port work? For example, a keyboard?

ToffoliGate

Also, what are your USB port settings? Disconnect your USB, then go in Settings > Privacy and security > Exploit protection > USB-C port > set it to "Charging only when locked" or, just now for testing, to "On" (remember to revert it to some other setting that meets your threat model after you're done with testing/backup).