I've wanted to resize the partitions on my Vista machine for several weeks now in order to gain a little more space for shadow copies on the C and D drives, but have been reluctant to do so after having read many threads about DD10 messing up Vista installations. I use this machine daily in my job and any interruptions would be a major problem. Tonight I finally just went ahead and did it and it all worked out perfectly. Here's what I did. 1. Old partition layout was [Vista 25 GB primary] [Data 25 GB logical] [Backups 99 GB logical]. 2. I wanted [Vista 40 GB primary] [Data 40 GB logical] [Backups 69 GB logical] 3. Create an image of the Vista and Data partitions using ATI. Verify the image. This is for insurance purposes! 4. Turn off System Restore on the Vista and Data partitions in order to delete the shadow copies and restore points as a means of making the partitions a little smaller. 5. Defragment all three partitions. 6. Quit Vista and boot into the DD10 recovery environment, manual mode. 7. Select the Backups partition and resize down from 99GB to 69 GB, leaving free space at the beginning of the partition. Commit and wait about 10 minutes for DD to finish moving the data in the partition up higher. 8. Select the Data partition and resize up from 25 GB to 40 GB. Move the partition's data to the right and leave free space at the beginning of the partition. Commit. 9. Reboot into Vista and check the results -- as expected. 10. Reboot into DD10 recovery environment and resize the Vista partition from 25 GB to 40 GB by incorporating all of the free space following the partition. 11. Reboot into Vista and check the results -- perfect! 12. Re-enable System Restore on the Vista and Data partitions. Create a restore point. 13. Run chkdsk to check all three partitions -- no errors or problems found. 14. Run Vssadmin to check the size reserved for shadow copies -- increased from 3.75 GB to 6 GB as expected. A couple of comments -- my disk's layout was originally created by the XP installer a couple of years ago and was later repartitioned by DD10. When I installed Vista, I did not let Vista reformat its partition, so it used the current layout which has the partition boot record starting in sector 63. Since I didn't relocate the start of the Vista partition during these operations, I did not have to repair the Vista bootloader; it just worked. Moving the starting sector location would have required a repair with the Vista DVD, as others have noted. It was nice to have planned this out in advance, thought about it for long enough to determine that it should work correctly, and then have it work out as planned.