Error 1516: "Partition improperly dismounted" appears randomly

Situation:
You are using your computer and you see an error message such as "Error 1516: Partition improperly dismounted (EA3905EC)."

Solution:
There can be more than one cause of this error, and each cause has a corresponding solution. Try these solutions in the order in which they appear.

"Dirty flag" set
This error can occur if the partition's "dirty flag" is set in a restart record in the journal file. This error may also be caused by a power failure or system crash while the Microsoft® Windows NT® operating system was writing the partition.

This problem can often be resolved by running CHKDSK /F on the affected drive. For instructions on how to run CHKDSK, read How to Run Microsoft's CHKDSK from the Command Line.

S.M.A.R.T. error detection
This error can be caused on Windows 2000/XP by the S.M.A.R.T. error detection feature. This feature is included in utilities such as CPUCool.

To fix the problem

1. Disable the S.M.A.R.T error detection feature in the CPUCool program or similar utility.
2. Boot to the Windows 2000 or XP installation CD, and at the Startup menu, press R for repair.
3. In the Recovery Console, type the following:
   
   chkdsk /p
   
   
4. When the CHKDSK process has finished, reboot the computer.
5. Run the program again.

The error should no longer be reported unless you start using the S.M.A.R.T error detection feature again.

Error occurs with PartitionMagic 8.0
If you encounter Error 1516 with PartitionMagic 8, first run CHKDSK /F on the affected partition. For instructions on how to run CHKDSK, read How to Run Microsoft's CHKDSK from the Command Line. If this does not fix the error, try running PartitionMagic with the /IFC switch, which causes file system errors to be ignored.

To run PartitionMagic with the /IFC switch

1. Boot from the first PartitionMagic rescue disk.
2. When you are prompted to insert the second rescue disk, press Ctrl+C to drop to the command (A:>) prompt.
3. Insert the second PartitionMagic rescue disk and type the following:
   
   pqmagic /ifc
   
   
4. Press Enter.

Last Modified: 02/09/2005