Hi Daniel,
That shouldn't be happening, let us help make this right. As you're getting a program error while opening a psd file, could you please let us know does it happen with every psd file or some specific files?
Where is the file stored? Could you try copying the file to the desktop and then try opening it in Photoshop?
Also, please let us know the exact version of Photoshop you're working on.
Regards,
Sahil