After running TestDisk

After writing a new partition structure, you have to reboot for the change to take effect. Check the filesystems and repair them if necessary.

Ext2fs/ext3fs

To undelete files, you can try e2undel

ReiserFS

If the superblock of a reiserfs partition is missing, it can be rebuild with reiserfsck --rebuild-sb device.

Linux/FreeBSD

You may have to update your /etc/fstab to reflect the new partition order.

Multiboot

You may have to update your multiboot configuration and reinstall the multiboot in the Master Boot Record.