Files not importing

Hey,
Whenever I try to import a file (.mov .aep .mpg etc) into a new project in Mocha I get the error message: Cannot import [file]. This file is corrupted or in an unsupported format. Does any one have a solution?
Thanks

Make sure your quicktime and your video card drivers are up to date, this error is usually because the format is not supported by your version of Quicktime. This includes formats such as WMV, DivX and XVid. The windows version of Quicktime does not support all Quicktime codecs, such as Apple Intermediate Codec and ProRes. When in doubt, try converting your footage to another basic format (such as Animation) or use image sequences.
Also, check to see you are on the latest point release of your product, as sometimes system upgrades (such as Snow Leopard) can cause issues with older versions of the software.
Cheers,
Mary