Just a quick one.
I was trying to add and deploy a WSP file.Both went well until i tried adding the webpart and i get the error
Web Part Error: No available sandboxed code execution server could be found.
After doing some joggling around i came to know i had to start the
Solution:You need to start the SharePoint Foundation Sandbox Code Service service instance from services on server..
This has to be done in the SP 2010 Central Admin > App Management > Service Apps > Manage Services on Server.
Hope this helps
**If you are unlucky and do get Web Part Error: The request could not be completed because the specified solution was not found.
Solution: Just retract the solution remove it and then add it back.(But make sure you start the right services though before adding the webpart)