Consider an instance, you try to run Uninstal.exe in real mode, but instead of expected behavior, you encounter an error message describing that Winundo.dat is missing or damaged. The error further gives you an option to continue. Clicking either of the options (Yes or No) gives you the below error message:
"Invalid system disk"
This error appears after the system restarts.
The above behavior is exhibited when the following set of conditions is true:
You have converted your primary drive to FAT32 file system using Drive Converter utility
You have run Uninstal.exe from Windows startup disk or restored it manually
You have run Uninstal.exe in real mode
You have installed Windows
You have used a third-party disk partitioning utility
You have run Uninstal.exe
In the former case, running Uninstal.exe replaces FAT32 MBR with backup of FAT16 MBR and you observe the above error messages. However, in the latter scenario, the issue is observed if partitioning utility affects the partitioning structure of the disk.
To resolve such issues, you need to perform these steps in order:
Recreate you primary drive using utilities like Fdisk.exe
Reformat the primary drive
Reinstall Windows and other applications
Restore data from backup
At times, you cannot restore from the present data backup. It might occur if backup is damaged or not updated completely. Thus, to cope up with such situations, you should use data recovery software. These are advanced data recovery tools built with indigenous technology to safely recover the lost information from logically crashed drives. Such tools provide you interactive user interface, powerful recovery features and several other added characteristics.
Stellar Phoenix Windows Data Recovery is a premier application to recover and restore lost data that supports Windows 7 (currently in RC 1), Vista, XP, 2003, and 2000. This read-only data recovery Software provides powerful features like Disk Cloning, Disk Imaging, Drive Status, RAW File recovery etc. It is compatible with FAT32, VFAT, NTFS and NTFS5 file systems.