If you can’t reproduce a bug on your own machine, the build machine is your insurance policy. Use it to verify bugs that you can’t reproduce on your workstation. Once you duplicate the bug on the build machine, figure out what’s different on your system. Once you’ve duplicated the bug, craft a test to expose it, and then run the test on the clean box. If you write the test carefully, you can even send it into the field to see if the customer can duplicate your results. Of course, if you can not reproduce the bug on the build machine either, then perhaps the customer has a configuration problem on their own machine. Start asking questions about the environment they’ve set up.
Tip 29: It has to work for everyone
I think it is irresponsible and lazy for developer to give up and say "it works on my machine" but I see it all the time.