SGS2 can't connect to PC for USB file transfer or Debugging mode I am an Android developer and I have been using my SGS2 for a while and I was accessing the debugging mode without any problem, until I broke my phone's screen. I found a repairer who replaced the screen with another. Since that day I cannot access my S2 neither on Debugging mode, nor on USB File Transfer mode. 

How can I fix this?

EDIT

It still charges when connected to PC, but no feedback in my Win 7. I tried with other computers and getting the same things ...
The description of the issue pretty clearly pointed to a hardware issue (the "repairer" having "messed up" / forgotten to re-attach some "connectors").

As reported back, this guess was correct: Taking the device back to him and have him check, he found the "missing link", repaired it, and the device is fully operational again now.