windows QUEUE MESSAGES error on open - The list of messages cannot be retrieved. Error: Access is denied

This can happen if the .NET Service removed the "Everyone" group from the permissions the private queue. Here are some steps you can take to resolve this:

1. Stop the MSMQ Service
2. Open the folder C:\WINDOWS\system32\msmq\storage\lqs
3. Find the file in this folder that describes your queue -- (incommingQueue)
4. Using notepad, open the lqs file for some other private queue that has good security permissions. (If you don't have any other private queues create one)
5. Locate the line in the file that begins Security=....
6. Copy the whole line to your clipboard (watch out for Word Wrap, this line will be quite long)
7. Open the lqs file for your problem queue in your text editor
8. Overwrite the Security=... line in this file with the contents of your clipboard
9. Save the modified lqs file
10. Start the MSMQ service

You should find that the problem queue now has the same permissions as the queue whose security settings you copied at step 6 above.