Install it on the server and run it as Administrator
Make sure the WSP package / DLL in the GAC is up to date
Copy the .pdb file from your build directory to the GAC folder Tip #1: use command line copy command Tip #2: map the windows assembly folder to a network drive to easily explore the inner folders
Make sure you have and account with the same name in both machines
Back to Visual Studio paste the server name in the qualifier text box (something like DOMAIN\username@SERVERNAME), hit Enter and the process list should popup from the server
Attach to the appropriate IIS process (w3wp.exe) or SharePoint Timer Job process (OWSTIMER.EXE)
Wait while symbol are loading and after that you should able to debug the solution and hit breaking points.
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