According to your description, your USB flash drive is probably now formatted as a Mac-only file system. So to fix your USB flash drive that works only on Mac but not on Windows, you need to reformat your USB flash drive in Disk Utility. Here's how:
- Insert the USB flash drive into your Mac.
- Go to Finder > Applications > Utilities > Disk Utility.
- Select the USB flash drive in the left sidebar.
- Select the Partition tab.
- Set Volume Scheme to 1 Partition.
- Click Option > Master Boot Record > OK.
- Type in a volume name and set Format to MS-DOS (FAT).
- Click Erase.
And before you reformat your USB flash drive, you need to back up your data. After that, you can insert it into Windows PC to check if the problem has been fixed.
If you forget to get data off USB, you can use iBoysoft Data Recovery for Mac to take back your data.
iBoysoft Data Recovery for Mac uses advanced and secure data recovery algorithms to help you find lost flies from your formatted USB flash drive. Here's how:
Step 1: Insert your USB flash drive into your Mac.
Step 2: Free download and open iBoysoft Data Recovery for Mac.
Step 3: Select the USB flash drive and click Search for Lost Data.
Step 4: Preview the search results and choose the data you want.
Step 5: Choose a location to store your data and click Recover.