Failed to Initialise the addin
Symptoms:
Shortly after opening a "Failed to Initialise the addin" error appears and the Mail Manager buttons are disabled.
Cause:
1. Outlook registry key issue
2. A version of Microsoft Office was replaced by an older version. Remaining registry keys from the newer version are conflicting was the older version.
Resolution:
2. Use the Registry Checker to establish if there are any missing or incorrectly set registry keys