How to format pendrive which is write protected: yahooanswers

1. Remove the write protection:
http://www.ghacks.net/2011/03/18/how-to-enable-write-pr...
2. Back up your important data form this pen drive.
Since format will erase all your data inside this pen drive, you should back up your data well. If you cannot access the inner data somehow, you could firstly try a free drive recovery tool to save the data. Honestly, my sister has tried it to recover his data from a memory card. She thinks it is really easy to use and useful.

You could get it there: -http://blog4mark.blogspot.com/2013/01/memory-card-recov...

3. Format this pen drive:
Right click “My Computer” =>Select “Manage”=> Choose “Disk Management” => Right click your drive on the list => format it.