We have now received the official statement from Nikon Europe on the incompatibility problem between newer 512 MB or 1 GB IBM Microdrive's and the D1x digital SLR. We first picked up on this problem when it was published on a Nikon Japan site and then later on an IBM compatibilty chart. Nikon Europe say, "The incompatibility has arisen as a consequence of a manufacturing change to a key component within the MicroDrive...". There's also a note that the D1x can be upgraded to firmware v1.01 which will solve this problem.