When using OpenText eDocs and opening an Excel file, when Excel opens it will pop up a message saying “Cannot run Macro DDEOpen”. I had this issue and after further investigation I found this small fix that will solve this problem.

Go to File > Excel Options > Add-ins
On the bottom there is the Manage
From the list box, select Disabled Items and click Go
You should see some items in that list, make sure you select those that are related to DM and click on enable.

After this just restart DM and excel and it should work.