To reactivate a mirrored volume
If the I/O errors are transient, you can try to reactivate the disk.
Open Computer Management (Local)
In the console tree, click Disk Management.
Computer Management (Local) > Storage > Disk Management
Right-click the partially failed disk, and then click Reactivate Disk.
The mirrored volume's status should change to Regenerating, then Healthy.
If the disk containing part of the mirrored volume does not return to Healthy status, see Replace the failed mirror with a new mirror on another disk
To open Computer Management, click Start, and then click Control Panel. Click Performance and Maintenance, click Administrative Tools, and then double-click Computer Management.
You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings may also prevent you from completing this procedure.