Description - essexcln.xll is a ESSEXCLN\r belonging to Hyperion
Essbase 18.104.22.168\r from Hyperion Solutions Corporation\r
I don't have the Addin. Before you try anything, have a look in
Tools > Macro > Security > Trusted Publishers
There are 2 check boxes. Tick them both. OK.
Try the program now.
I've found a solution.
In Excel, Tools > Add-Ins
Uncheck the Addin for Hyperion EssBase. Apparently, the Addin does not behave if it is already in Excel. It may be a security issue.
This routine adds the Addin when the before you try to access it.