Just ran in to an excruciatingly painful issue with W7 RC (build 7100)... The Disk Management utility (via control panel>admin tools) gets confused with removable drives that have multiple partitions. The setup: W7 7100 16GB SD card - 3 partitions, 4gb ext3/1gb linux swap/10gb fat32 Partitioning and formatting was originally done with a linux system. I was looking to transfer some files from the W7 box on to the fat32 partition so I put the SD card in to the W7 box. Initially, W7 would not recognise the fat32 partition and silly me thought that perhaps I hadn't formatted it, so I loaded up the W7 disk manager, which correctly identified the 3 partitions on the card and their sizes, but reported all 3 partitions as unknown filesystems. I expected the ext3 and linux-swap partitions to show as unknown, but the fat32 showing as unknown rather empty or such seemed a bit odd. Guessing that perhaps the linux partitioning tool I used may not have created the fat32 filesystem correctly after all, I instructed W7 to format the 10gb partition as fat32 by rightclicking the partition, selecting format, and telling it to use fat32 as the filesystem. After OKing the format, the disk management tool froze for a second as it has done in the past when initiating a format, and then the status of the 10gb partition changed to formatting. A few moments later, the status for the 10gb partition goes blank, the filesystem of the 4gb!!!! partition changes to fat32 and its volume label was cleared. Rightclicking on the 10gb partition and selecting info/properties produced an error message saying that the disk manager's information was not currrent and that I should try clicking the refresh button/restarting disk management/rebooting the pc. Trying all 3 of those steps just resulted in the same message coming up. When I put the SD card back in to the linux machine that had done the partitioning originally, it showed the card as having an empty 4gb fat32 partition, a 1gb linux swap and the 10gb fat32 partition that it had created initially. This has resulted in the complete loss of the ext3 filesystem that was in the first partition of the SD card. After realising that my 3-4 hours of work on the ext3 partition were gone, I set out to see whether this issue was confined to SD cards, or would extend to anything that W7 identifies as a 'removable device' I had a smaller SD card and a USB stick floating around, both 4gb. Using the linux machine, I partitioned each in to 3 partitions, 1gb/1gb/2gb, and then attempted to format the 2gb partition on each as fat32 using W7. In both cases, W7 formatted the first 1gb partition, leaving the other two partitions untouched. Why is the W7 disk manager differentiating between HDDs and 'removable media' in its operation? Considering there is nothing at all to indicate that it exhibits this behaviour, it is an issue that will cause heavy data loss to anyone using multiple partitions on a usb stick or sd card. Has anyone else experienced similar issues? or perhaps it might work for you?

Hi Tempestrix,I have a 4 gig usb drive I'll try this out on to see if the same happens to me. If so, that would befrustrating (and valuable to know ahead of time!) Sorry for your loss.....I'll re-post with findings sometime this weekend.Regards from the Valley of the Sun.

The same happened to me. So everyone,be aware that the Fat32 or NTFS partition on removable media has to be the leading partition.Regards from the Valley of the Sun.

Thanks for confirmation. I really have no idea why disk management would treat removables differently to fixed disk devices.... especially considering the capacity of removables these days. Marked as answer to confirm bug for anyone that might come looking

BUMP! Mentioned this issue in passing to a colleague and decided to have a look and see if it had been fixed in retail. Partitioned an 8GB usb stick (using a linux PC) into 2gb/1gb/4gb partitions of ext3/swap/fat32, plugged it in to this PC (running Win7Pro), found the same issue - Disk Management will see 3 unknown partitions, and attempting to format the 3rd one will actually format the first partition. Just for completeness sake, I also repartitioned the usb stick with a GPT partition table instead of MBR and recreated the same partitions (2/1/4). When I plugged it back into windows, it would not see the third partition AT ALL and actually reported the size of the total disk as 4GB smaller... Given that the problem was originally reported in build 7100 I'm honestly surprised that it STILL hasn't been fixed.

just had the same problem and managed to solve it by formatting the SD card in my digital camera :) not ideal but works like charm!