This knowledge base article addresses the issue of encountering the "Error while Reading bitmap file for the disk" within the BDRShield software. This error can manifest when the bitmap file is missing from its designated location at "C:\ProgramData\VembuHyperVCBTStore" or when the VembuCBT drivers become corrupted.

The aforementioned error message may arise under the following circumstances:

1. The bitmap file has been inadvertently deleted from the specified directory, "C:\ProgramData\VembuHyperVCBTStore".

2. Corruption of the VembuCBT drivers, which can lead to this error.

To address this issue, please follow the steps below:

1. Reinstalling VembuCBT Driver:

1. Open the command prompt with administrative privileges using the "Run As Administrator" option.
2. Navigate to the installation directory of the Vembu Integration Service.
3. Execute the following commands to first uninstall and then reinstall the VembuCBT driver:
   
1. `VembuInstallationLocation\Drivers\HyperV>HyperVDriverUtil.exe -uninstall`
   
2. `VembuInstallationLocation\Drivers\HyperV>HyperVDriverUtil.exe -install`
   

2. Verification:

1. After executing the commands, input "fltmc" in the command prompt and press 'Enter' to view the list of drivers. Verify the presence of the VembuCBT driver.
   

3. Performing Additional Backup:

1. Given that the VembuCBT driver has been reinstalled, it is crucial to conduct an extra full backup for all backup jobs configured on the affected host.
   

Note: This solution has been provided to tackle the "Error while Reading bitmap file for the disk" issue within BDRShield. By meticulously following these instructions, users can resolve the error and restore the optimal functionality of the backup application.