I have a few colleagues who work with AutoCAD LT on daily basis, and some of them were having issues with it.
One of the most annoying issues in AutoCAD was -> unhandled exception e0434f4dh.
I browsed support forums, blogs and finally found solution here.
In my case unhandled Exception e0434f4dh happened on startup. AutoCAD almost finishes with loading and then “unhandled e0434f4dh Exception at 770570cdh” message is displayed and AutoCAD crashes.
The solution for me was in editing registry value. As always, be careful when editing registry because you can seriously damage your OS if you don’t know what you are doing.
In the registry editor go to the following registry key:
HKEY_CURRENT_USER\Software\autodesk\AutoCADR18.0\ACAD-8000:409\WebServices\CommunicationCenter
In the right pane of the registry editor you will find a key ”LastUpdateTimeLoWord” with a dword value of 4be447d0 (or something similar)
Double click on that key entry and enter 0 (zero). When you confirm the change, the value for a key should be 00000000.
After exiting registry you should be able to start and work normally in your AutoCAD installation.