Although strictly not a MFDB topic, this is very important for users of Windows Vista along with a Canon 1Ds or 1D.
On Canons "Self Support Centre" part of the european webpage, the case id: 67464 states:
"Thank you for using Canon products.
We have discovered that original image data disappears on PCs running Windows Vista TM, the new OS from Microsoft, if TIFF (RAW) images shot with EOS-1D or EOS-1Ds digital SLR cameras are rotated or edited under certain circumstances. Customers who use affected products should be careful and follow the countermeasure below."
More information can be found on Canons website on how to avoid this, follow the link here and enter the case number:https://self-service.canon-europe.com/ce/pages/