I have my C drive full... then I add another HDD but when I try to install a program installation still head to C drive... how can I make E drive as the default installation drive E(2nd HDD)... :confused:

You MIGHT be able to using a Registry hack, which I don't recommend. It might also require moving the Program Files folder which, again I don't recommend.

Even though, almost all programs default to C:\Program Files in their installation, almost all offer the ability to change the directory. So just change the C to an E

If the Windows directory is on your C drive, then you will always need room on that drive for installs of Win software (DLL's etc). Offload non windows stuff from your C drive to new drive to make room. Then as you install new software, when it asks you where to install, you can point to your new drive.

OK thank, But I already did regedit before I've read this but any way thankz...