Alex Pankratov :
Jul 02, 2018
FindFirstFileEx() failed with 87
This error means "invalid parameter", which in this case refers to the path of either your source or backup locations. For example, C:Folder instead of C:\Folder... that sort of thing.
Paths are checked by the program for obvious typos and mistakes when you are creating a backup job (including the kind from above example), but it looks like you managed to slip by these checks somehow.
Basically, double-check your From/To paths in backup settings.