The problem first appeared in Vista after upgrading to V 6.12.34 when I found that, whilst everything worked as expected when logged in as an Administrator, when I logged in to, the more secure, user account(s) BOINC would screw up the existing work units and attempt to download a fresh batch, (see message 1152236, etc.). XP systems were unaffected, (including a system which dual booted with Vista), as were my Windows 7 machines. This was not resolved and I got around the problem by leaving the Vista system running V 6.12.33. Not ideal but it worked.

When I upgraded to V 7.0.25, however, I now found the problem had not disappeared but had become worse and also affected my XP installations. Once again, strangely Windows 7 was unaffected.
This time, in addition, I did not have the option of having a mix of versions since the version 7 files are not backward compatible with V 6.

With some time spent trying various configurations and options, I came to the conclusion that the problem was because of file access issues.

My solution has been to make all "users" into members of each of the restricted boinc groups, i.e. "boinc_admins", "boinc_projects" and "boinc_users".
Making users members of only "boinc_admins" is not sufficient, (contrary to logic).
This solution may not be technically correct but it works and is reasonably quick to implement.
Those running the more basic versions of Windows without the means to directly manage user accounts will need to follow the instructions offered by Jorden at http://boincfaq.mundayweb.com/index.php?language=1&view=492&sessionID=efa6aecf8245a3bebc06b657e914cca0

I hope this helps anyone also struggling with this problem.

It would be helpful if the BOINC installer applied the appropriate permissions during the install. They must, surely, know that we are not meant to do our normal day to day working logged into a Windows Administrator account.

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The majority of the time, I've never had an user permission issue so long as I selected "Allow all users to control BOINC" during the installation process of BOINC.

The few times where it wasn't working properly, simpy adding the users (or using "All Users" as you did) to the "boinc_admins" security group fixed the problem. Never had to go any further beyond that.

The other way to do this is to make certain that "Allow all users to control BOINC" is checked in the installer. The installer then does these steps for you.

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