Acronis Backup Products: Warning "Error: There is a double slash in the path"

1. You use Acronis Backup 12.5 Update 3 (Build 10130) 
2. You run run an application-aware backup of a disk with MS SQL database
3. You receive a warning: Error: A double slash in the path. 

   and the following error in logs:Message: Problems detected that may cause a VSS snapshot failure.

(!) This article applies only to the case when you receive both the error and the warning specified above.