addressed PM feedback

Author: AbhishekMallick-MS

articles/backup/sql-support-matrix.md

@@ -43,7 +43,7 @@ _*The database size limit depends on the data transfer rate that we support and
 * TDE - enabled database backup is supported. To restore a TDE-encrypted database to another SQL Server, you need to first [restore the certificate to the destination server](/sql/relational-databases/security/encryption/move-a-tde-protected-database-to-another-sql-server). The backup compression for TDE-enabled databases for SQL Server 2016 and newer versions is available, but at lower transfer size as explained [here](https://techcommunity.microsoft.com/t5/sql-server/backup-compression-for-tde-enabled-databases-important-fixes-in/ba-p/385593).
 * The backup and restore operations for mirror databases and database snapshots aren't supported.
 * SQL Server **Failover Cluster Instance (FCI)** isn't supported.
-* Azure Backup supports only back up of database files with the following extensions - _.ad_, _.cs_, and _.master_. Database files with other extensions, such as _.dll_, aren't backed-up because the IIS server performs the file extension request filtering.
+* Azure Backup supports only back up of database files with the following extensions - _.ad_, _.cs_, and _.master_. Database files with other extensions, such as _.dll_, aren't backed-up because the IIS server performs the [file extension request filtering](/iis/configuration/system.webserver/security/requestfiltering/fileextensions).
 
 ## Backup throughput performance