file-format module cannot parse the file

I've just attempted to open a .tif file with Photoshop 7.0.1 and i get the following error:

Could not open "file name.tif" because the file-format module cannot parse the file.

If i open the file in Paint.NET and resave as a .tif it opens fine, unfortauntely the reason i need to open in Photoshop is so i can edit and save and control teh compression which Paint.NET doesnt allow.

The .tif files are being created by a scanner