I'm using a laptop. Runs on windows vista. The internal HDD is split into 2 partitions- it was this way when I purchased the laptop. The 2 partitions are as follows- C:\ (OS) and D:\ (Data) The first partition contains the operation system, and had initial programs upon PC purchase, as well as drivers and such. This partition is very small, with only enough room for such as described above. The 2nd partition is the larger, remaining portion of the HDD- where the user would install additional programs and store data files. Both partitions are equally accessible by the user. Last night I was running partition doctor on an external 1TB HDD. (This is not the issue at discussion, but may have been part of the cause.) The external HDD uses an external power source- requiring an outlet to run. Given my current location, I am unable to have both the external HDD and the laptop plugged up- during part of the partition doctor operation, the laptop battery was running low, so I stopped the operation and shut down the laptop for the night. However, when I booted up the laptop the next morning, I was prompted with a "system resume" option. This has not not been the first time I had to start up my computer with a system resume due to a battery drain or unexpected computer shut down. When the system booted back up, the vista prompt was up- "The following programs are still running- Shut down / Cancel", indicating that the laptop didn't shut down the previous night, but instead the battery had died causing the laptop to power off incorrectly. I proceeded with powering up the computer- I clicked cancel. Immediately, I noticed some things out of place. Some programs that were scheduled to start upon system start up failed to do so. Also, my taskbar and windows were in the classic windows view. MSN messenger proceeded to reinstall on it's own. As well, a 'new device was found' window popped up, and a disk drive was 'ready for use.' As I was thinking a moment, gathering what was going on, the computer came up with a blue screen... and rebooted. I went to my computer only to find out that the Data: partition was missing. I then went into disk manager to see if it was recognized there- and it was, but, as 'unallocated' I also went into device manager... it appears there, too. However, there is a SCSI/RAID host controller failure. My next step I took was to reboot the computer. This didn't help. I then used a system restore point. This didn't work either. I have 2 options I can live for- fix the issue that is causing the partition to fail to show up, or... recover all the data from the partition, store the data on an external HDD, and then format the currently failing partition, then place the data back onto the partition. Any help would be much appreciated.