I upgraded my version of BOINC from 6.10.58 to 6.10.60 a few days ago. So I started it up normally, and thought that everything was going to be fine. Next, BOINC said that it couldn't connect with the BOINC client.
I did some troubleshooting, first by looking at the service for BOINC on my computer (it was there, and it was set to automatic start). The account that it was set to use was the boinc_master account, so I also looked at whether the service could start properly by starting it from there. It gave me an error:
"Windows could not start the BOINC service on Local Computer. Error 1609: the service did not start due to a logon failure"
I looked through the user profiles in Windows, and found that the user accounts/profiles for BOINC were somehow gone.
I have attempted to reinstall BOINC to no avail, can someone help me?

System:
Windows Vista Home Basic (UAC on)
Windows Firewall
Core 2 Duo E4700
Nvidia Geforce 9300GE, driver version 270.61

The BOINC Limited User accounts aren't showing in the User Accounts & Family Safety menu in Windows. So if you were looking there, then that's normal.

Instead, open a command line window (Run->type cmd, click OK).
Next, type in the command line window the following command: net localgroup and hit Enter.
These will show whether or not the BOINC user accounts boinc_admins, boinc_projects (with extra 's') and boinc_users are installed.

boinc_master and boinc_project (without extra 's') are User Rights Assignments, not User Accounts.
They will allow:
-- boinc_master: Deny logon locally, Deny access to this computer from the network, Log on as a service and Bypass traverse checking;
-- boinc_project: Deny logon locally, Deny access to this computer from the network ;

To see which ones you have, do the following.
In the command line window, type c: and hit Enter.
In the command line window, type md sarge and hit Enter.
In the command line window, type gpresult /H C:\sarge\GP.html and hit Enter.

Next use Windows Explorer to go to C:\sarge and open GP.html with your favorite browser of choice. This command will show the Group Policy Results in a condensed form. Check if the boinc_master and boinc_project URAs are showing here.

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Hmm that's odd.
According to net localgroup it says that boinc_admins, boinc_projects and boinc_users are present in the aliases part.
However when I type in gpresult /R (not the one you suggested, as it said that /H was not a valid argument), the only security group present (apart from the other non-BOINC related accounts) is boinc_admins.
Did the installation go awry, or did I botch up something?

OK, I checked that command in my Windows 7 Ultimate, so that may be why the command didn't work. I do know that on some Windows XP/Vista/7 Home systems the installer seems to be unable to set the user rights assignments correctly. The developers are looking into this, but seem to be stuck as it doesn't happen all the time.

I can only assume that this thing also happened on your Vista Basic.
How to fix that? Add the members to the correct group.

Start->Administrative Tools->Computer Management->Local users and Groups->Groups.

Double click on any of the groups to open their contents.
boinc_admins should have your account (the installing user account), Administrators group and boinc_master.
boinc_users should have for Public installs: Everyone; for Private installs: nothing at all.
boinc_projects should have boinc_project.

To add an account, click Add..., click Advanced, click Find Now, find the account in the list and single click it to select it, then click OK, OK and OK.

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I managed to follow through to the Start -> Administrative Tools -> Computer Management steps, then I couldn't find "Local users and Groups".
Later, I realised why. Vista Basic, doesn't have that function.

http://windows.microsoft.com/en-US/windows-vista/User-groups-in-Windows

That explained why I couldn't find the option. I suppose I'll have to be content with running BOINC in normal instead of protected mode then.

Well no, then you return to the command line. :)

The net localgroup command is very powerful. One can add users to or remove them from groups this way.

net localgroup group_name UserLoginName /add

So in this case, it's:
net localgroup boinc_admins boinc_master /add
net localgroup boinc_admins Administrator /add
net localgroup boinc_admins SargeJohnson /add (Or whatever your Windows account is)
net localgroup boinc_users Everyone /add
net localgroup boinc_projects boinc_project /add

I will check with the developer how one can change the URA through the command line.

Now, I must say that when you install BOINC as not a protected application execution option, that the only account that will be installed is the boinc_admins account. The other accounts will only be installed on a service or protected application execution installation and you will have to choose this one yourself, it won't be enabled automatically, unless you had it running before and you're doing a BOINC upgrade installation.

Else do check each time you install BOINC what its installation is going to be, 3rd screen in the installer click Advanced.

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Err, ok I reinstalled BOINC with the Protected Application execution option checked.
However, when I try to start the service for BOINC (even though its supposedly set to Automatic, it didn't start on installation or startup of BOINC, so I had to start it manually by going to Services), it gave me a logon failure. Basically, the error message is the same one as the one in my first post for this topic.
I checked the properties for the BOINC service, and it was supposed to log-on using the boinc_master account (the default option, I didn't touch that).
So now, BOINC cannot run any projects' applications, and I have to open BOINC.exe in a separate window using my account (not using Administrator rights definitely) before I can run BOINC Manager and the Manager can see BOINC.exe, and therefore run any project.
Help please? Thanks.

You know what? Best remove everything before reinstalling BOINC.
Do not use the automated option as that will delete your data directory as well, that's not something we're trying to do.

Use this FAQ to fully uninstall/clean prep, then reinstall BOINC 6.10.58; 6.10.60 only has some screen saver additions. Plus 6.12 is now really quickly approaching (I hope).

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Well...yeah, I did everything you said there (apart from the deletion of the BOINC ProgramData folder, I moved it to C:\Program Files\BOINC before restarting the computer to complete uninstallation). Same error, same scenario as message 37633.
This is kind of getting frustrating....

All right, hold there. I'll contact one of the developers, see if he has any further suggestions.

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