I would recommend that you fully format that USB or throw it away. The freeze is as MCShield is try to delete the malware
When the time I don't have MCShield, this freeze was still happen, and in my USB there are some important documents that I can't throw it away now.
Do you have any idea how to "fully format" it ? I tried format it but after few days, the symptom still occur (like I say in #1).
Supposing my computer is having virus that bind into USBs, so that even I throwing away this current and buying a new one, it's still infect the other, so what can I do ?