One or more bad blocks were detected and skipped

During a backup using Veeam Agent for Microsoft Windows, each block is read. If a block is not readable (i.e., corrupted), Veeam Agent will skip that block and throw a warning message.

Unreadable blocks on the disk may indicate that the disk is unhealthy, and replacement may be required. 

The NTFS file system stores information about bad blocks in a $BadClus metadata file. More information about NTFS file system metadata can be found here.

Note: The $BadClus metadata file is backed up by Veeam Agent for Microsoft Windows. If a bare-metal restore is performed to a new drive, the $BadClus metadata is restored. To update the $BadClus metadata file, run the command shown in the solution section of this article.