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On the PC which is experiencing the issue, open Windows Explorer
Navigate to the following path:
Windows 10-8: C:\Users\User Name\AppData\Local\Nimbus\Cloud Document Management - CDM\Temporary Data
Search for any / all files that end with “JSON.txt” in ALL sub-folders. Once located, you will also find that there will be a matching file with the extension of .msg, which is the outgoing message.
If the message is not in your Outlook Outbox, please delete both files (with the JSON.txt and .msg extension).
Log out of Outlook and then restart Outlook.
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