psx rar or winzip files

hey guys im just wondering if any else has a problem with the psx rar files. it seems that almost every1 i download is a bad rar and will not open. is this normal/? the only 1s ive got to work are tombi and smackdown others i have tryed like air combat and hogs of war are bad roms. is this my pc or a real error with the file? thank you for your fee back
dale

What are you using to extract them? Tried downloading it using a different method (manager etc.)?

make sure you have the latest version of winrar.