If Add2Exchange was working and now it's not, post here.
Error: you receive an error in the application log similar to the following:
Faulting application A2E Director.exe, version 126.96.36.1990, faulting
module EMSMDB32.DLL, version 11.0.8161.0, fault address 0x000132a8
Most common Cause: Outlook CDO components are installed.
Solution: Remove Outlook CDO, unregister incorrect cdo.dll, re-register correct cdo.dll
also, it is always wise to do all the critical MS updates to the Exchange server and replication server and reboot.
Next, please see the link for possible antivirus in the way:
If still not working try the next solution(s)
Use this solution only if the Console does not open, else, go to the next solution.
In certain exchange environments, the Add2Exchange Console will drop from memory near the end of the loading phase and never display.
We have identified this to be an issue with a supporting file for the CDO libraries on the given server. Microsoft is aware of the issue, and has released a hotfix which includes this fixed supporting file. However, on some systems, this hotfix does not install correctly and the supporting file is not updated.
Microsoft has provided us with an unsupported emergency replacement for this supporting file, emsmdb32.dll. This file is available at ftp://ftp.diditbetter.com/emsmdb32.zip. This file should only be used in the exact circumstance described above, and no license or warrantee is provided by Microsoft for the use of this file. Neither Microsoft nor DidItBetter.com Software may be held liable for incorrect usage of this file.
To update the supporting file:
Next Option 3: If neither of these options work, a "startover" and resync is the next step to work. Do not delete the relationships, License the A2E Toolbox and run a Startover from the paid side.