Emails won't send.

My last 3 emails won’t send. I keep getting a box up telling me that I still have messages in my outbox. However, I can’t find my outbox. Trash, sent and inbox are still there but outbox has vanished. I need to cancel these emails if possible. Don’t be too technical as I am a pensioner!

The “outbox” is probably under Local Folders.  

To see that:
Menu > Tools > Settings
General
Check Show Local Folders

Then you can remove the stuck message.
I have the same problem with my Exchange account since upgrading. I had to switch to a different client.

Thank you so much. That worked!