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If your Transcend flash drive is write protected, copy all the files to a HDD for backup.
Then you can download from the Transcend website a recovery program that will reset the flash drive.
From the transcend web site:
"Please download the Online Recovery Tool from Transcend Download Center to re-initialize your JetFlash.
Please check that you download and use the correct version of Recovery Tool for your JetFlash. You can also download the Recovery Tool from the model page according to your JetFlash model.) Note! This step will erase all the data stored in your JetFlash, please backup your data first."
After the flashdrive has been recovered, and free to read and write to, copy back your saved files, ad you are back in business.