Help with Frequent "Invalid class string"

Hi all!

I am hoping that someone with a little computer-savvy might be able to make my life a little easier.  My problem is with “Invalid class string” (ICS) and it frequently visits my workstation, destroying communication between the two programs!  It’s starting to feel like Word/EndNote have a celebrity marriage…

Problem is I haven’t found the symptom of what destroys communication at this point.  I will put my thoughts below, but I hope somebody can give me a permanent fix!


  • Windows 7 Pro with me as admin & UAC to the second lowest sensitivity
  • Office 2010 Pro
  • EndNote X5 and one big library for numerous documents at once (the library doesn’t move location on Windows)
  • EndNote does not communicate with the internet or university library
  • colleagues do send me documents likely edited with different E/N libraries of different versions, say, X2
  • it’s an older work computer, so I DO notice older EndNotes sitting unused in Program Files (I set X5 as default)
  • seems to happen “randomly”, but I usually notice it by trying to fiddle with the Style tab in Word as biblio is the absolute last thing I ever do (also means that many times, this has happened when the doc has no biblio yet)
       - since I don’t often play with the biblio, I don’t know if there is a specific trigger; of the 20 times I started my docx, it could have happened on time 2 or time 20 OR the last time I restarted the computer, or etc…
  • I usually fix it by closing both and in Program Files (1) E/N as Administrator (2) Word as Administrator (3) send random reference through E/N to Word (4) close both & open normally

So it happened again in the middle of scanning something and to elaborate, it results in litterally a hundred or so popup windows exploding through Word2010 and paralyzing the program for sometimes 30 minutes even.  *usually seen on opening of Word when E/N is already open and running.

Aaaand there it is!  SO can anybody suggest why I get the Invalid Class String error every time I create a new Word document??