Over write common folder

Hi All,

I have build a product with newer version number . According to the new build it has new version dll's.
"program files/common folder has four dlls". While upgrading from older version to the newer version the files in the common folder alone is not getting updated to new version files. where as file present in some other folder is updated. According to one of the forum one guy was telling like it if the files present in folder is key file's then all the files should be updated else it wont be updated. So i removed all the key file to normal files and also tried with option always overwrite.


But still no hopes.
The file in the common folder are not getting updated.
Please someone help me to solve this problem.