I've suffered from file corruption before, I find the occassional jpeg file that has a working thumbnail but on opening the file is corrupt - mostly they still open and a bit of cut and paste work can stitch shifted blocks of pixels back into the right places. Consistently I've found the pictures have been like that for so long that the issue pre-dates my earliest backups.
I am yet to discover any software that can automatically detect corruption and having pictures on a RAID array seems to make no difference - the drives system must thing the corruption is deliberate.
I had problems in the past when using ZIP compressed TIF files - nice and small but minority support - eg Windows Media Center / Media Player / Explorer cannot cope so not much good on the usability front.
Today I have discovered another problem with TIF files, namely Photoshop reports "this file format is not supported", similarly Elements (CS3 & 7.0 respectively) so presumably the code is the same. The very files affected are some of my favourite pictures and after various attempts at convincing Photoshop to open them I downloaded some alternative products - XnView, GIMP and Irfanview. I've used Irfanview extensively in the past as it's a great lightweight tool particularly for bulk format conversions, TIFF files not problem. Xnview, great looking tool & lovelly screen display (my picture looked great) and also no problem with TIF files. Finally, GIMP, I hadn't expected much as a Linux port particularly as last time I looked at Gimp, on Linux I didn't need to spend much time concluding it was pants. However, the current version looks great (an obvious downside is that all of the initial panes either appeared partly or fully off screen and the loading time was measured in aeons) - a clean interface and clearly based on Photoshop, enough so that I think it will be worth investing some time as the interface feels, if anything, more user friendly than Photoshop but not as amateur as Elements, so thumbs up Gimp, it too handled my problem TIF files perfectly.
So, come on Adobe, why does Photoshop take a disliking to some TIF files at random, furthermore, until today those files were both created in and only ever editted in Photoshop so what changed? Googling shows I have not been the only one suffering this bizarre issue.
Anyway, to show the files are alive and well here are my pictures :
this was a clematis growing unpruned at my first home, a woody mess most of the year but when flowering a riot of bloom and the other picture is that of an owl taken at a swan rescue centre display in Christchurch when they were clearly short on swans.
As a worthy footnote, I have used Microsoft's volume shadow service on Windows servers and have duly left the capability in place for Windows 7 on my laptop and that did come the rescue in finding earlier copies of my file which I could use for comparison purposes - not my only backup but a very handy emergency option - so for Windows 7 users don't feel tempted to turn off