David I guess that may work, but it still leaves the question as to what is creating the error. It suggests that there is still something lingering that is tied in with the install of the Dictionary that is trying to create a tray icon from something that now no longer exists. Resetting the Notification Icon might not help the problem, the Error message "ORDBOG" means DICTIONARY, so it suggests that there is something related to the dictionary still there.
tonyvella, I would check your startup items (Start>All Programs>Startup) and see if there is anything related to the dictionary in there.
The other place to check is the Microsoft Config settings (it lets you enable or disable startup items or services which load at startup, it also lets you get to Safe Mode if you can't get the whole F8 thing to work).
Hit the Windows Key and R at the same time and type "msconfig", click the startup tab and sort it either A>Z by Startup Item or by Command. If there is a program trying to start from the same location as the dictionary was installed to then I would just disable it. This is safer than deleting the registry key as it can be enabled again.
Speaking of the Registry Key, from the looks of a few of the names and values, it looks like it's just a place where the dictionary stored its settings: X&Y Screen Position, Side by Side Dictionaries, Last viewed Dictionary etc. Probably not used by anything else considering the names of the folders etc, but I would still do the startup items check before deleting a registry key.
(As for "is it safe to delete registry keys": A lot of people say that Windows suffers more when you delete unused keys and don't defragment and compress the registry afterwards. Leaving redundant code in it is not as performance hitting as leaving big holes in it. Besides that I found out exactly why you can't just dive in and delete registry keys that to you seem empty and/or unused, somehow I had managed to get my login screen to only display a single user with the "Other User" being a Text box to type the Username, I deleted about 2 or 3 keys to try and set it back to having all three user accounts on the logon screen and and did indeed fix it, but in the process broke my Windows 7 License & it couldn't reactivate so I had to ask a friend for a copy of the registry keys from his PC, which luckily for me fixed my license).