Since the BOINC uninstaller does not clean up after itself, you're stuck with a lot of directories, registry entries, user rights assignments, and user accounts that you may or may not know about.

A year ago I asked if the uninstaller couldn't clean up after itself. Since then that Trac ticket has moved through a couple of milestones and is now waiting for 6.12 ... not really nice.

I have adapted the WinSix clean up logic page in the BOINC Wiki to show what steps need to be done manually. I also put those in my BOINC FAQs. Still not very satisfying and a problem for new users, or those not too computer savvy.

So, today I added an automated option for that in my BOINC FAQs, the BOINC Cleaner V1.zip. With thanks to Gundolf Jahn and Richard Haselgrove for testing it.

It will assume you uninstalled BOINC through Add/Remove programs, then downloaded this utility and started it. What it does is:
1. Uninstall the BOINC user accounts and groups.
2. Use the Windows 2003 Server Tool NTRights.exe to delete the User Rights Assignments.
3. Kills boinctray.exe if it is still running.
4. Read the BOINC Install directory and Data directory paths from the registry and subsequently delete both directories and all files and sub-directories included.
5. Finds and deletes the BOINC_Master directory or directories in the Documents and Settings directory (works on foreign language Windows as well, where the "Documents and Settings" directory is set in that language)
6. Deletes all BOINC related keys from the registry.

Since I am using the Microsoft NTRights.exe tool, I am not sure if BOINC can distribute it. So I will keep it available from the BOINC FAQs pages for now.

Do read the Readme.txt file for instructions on how to use it.
Don't forget to reboot your computer after you ran the utility, to finalize the Windows process of getting rid of the user accounts.

It is made for cleaning up after BOINC 6, but Gundolf tested it on BOINC 5, where it works as well, although it will then throw some errors on things it cannot find. It works on Windows 2000, XP (Home and Pro), all Vista and all Windows 7.

A future version will do everything automatically, from uninstalling BOINC through cleaning all the stuff to giving you the option to reboot or not.

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