Photoshop :: CS Extended Can't Open Some

I have created a new PSD file and worked on it and finally saved the file, but now i can't open the file any more. PS always fails to open the file, because of an internal error.

I have tried to open some other PSD files, but 3 of 4 files (on my current HDD) didn't work to open and i don't know why. All of those other PSD files are at least 1 month old and PS could open these files. The last time i have opened these files was two weeks ago. The one PSD file, that worked has the following properties:

image: 1179x1528, 72ppi,8bit,RGB, 15,04 MB

and the files that don't work have the following properties:

image1: 454x340, 71ppi, 16bit, RGB, sRGB (profile), 1,17 MB

image2: 1280x1024, 71ppi, 8bit, RGB, sRGB, 1,92 MB

image3: 1191x1644, 71ppi, 16bit, RGB, sRGB, 12,02 MB

I have got, the meta-data out of Adobe Bridge. I can see the preview Image and the thumbnails in the open-dialog of PS. I tried to open the file with other applications like Paintshop Pro and PhotoImpact and both couldn't open them. Paintshop Pro quits, because it doesn't support the "color model".

I don't know, what else i can do to open these files. I looked around the forum but couldn't find any solution for my problem.