Originally Posted by andyvand

On a 32-bit only AMD system you should use a custom install with the installer and check the option for the patched CoreServices.
Also use the UPX for doing stuff but download the one I'm posting right now...
It has also LZMA support (for --ultra-brute) and has stuff built this way that it will work like a regular standard UPX.
If you encounter files you can't pack you can use the following command to pack it anyway:
upx --force <binary>
The new one can also pack Skype (which the previous one can't do...)