...HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Windows/CurrentVersion/Run. Verify that you have sufficient access to that key, or contact your support personnel"

i get this message half way through installing boinc.

does this mean i have an older version installed or what? because i dont think i do. :S

It may mean you have an older version installed, but it's not necessarily that (do check in Add/Remove programs if you have something called BOINC installed. If you do, uninstall it). Looking around the web it's a permission problem.

So, open the registry with regedit. (Start->Run, type regedit, click OK)
Navigate to HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Windows/CurrentVersion/Run and right click on it, select permissions.
In the window that now opens, make sure your account name is in there and that it has full rights.
Go to the Advanced button and uncheck the "Inherit from parent." option. Click OK.
In the top box called 'Group or User names' it needs to list both Administrators and System and they both need to be given 'full control'. Add or change the groups as needed. Don't change any other groups that may be listed.

When that's done, close regedit.
Try to install again.

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