I reinstalled Vista after upgrading to a Core i7 860. Before the upgrade I was on the same Vista version and using BOINC 6.6.36. After installing BOINC 6.6.38, I connected to two projects and began processing 8 workunits as expeced. All of a sudden, I get the message, "BOINC is attempting to communicate with the client." When I restart BOINC it tells me I need to add my user to the "boinc_users" group. Some web research informs me Vista Home Premium can't manage user groups - you need Office $ or Ultimate $$ for that. I tried uninstalling and reinstalling 6.6.38 - getting the same results. I ended up uninstalling and reinstalling 6.6.36 and that worked.
So I'm fine now; I'm posting this as a bug report and as a warning to other Vista Home users.

Um... when you first install BOINC 6, you need to do a reboot to let Windows know about the limited user accounts that the installer made for BOINC. Did you do that reboot?

BOINC 6.6.36 and 6.6.38 use the exact same installer, which make the exact same limited user accounts.

Also, the BOINC Manager (GUI, boincmgr.exe) and client (boinc.exe) need to be able to talk to each other on TCP port 31416. They need to be allowed through the Windows firewall or whatever other firewall product you use. On top of that, boinc.exe needs access to the internet on TCP ports 80 and 443.

The message that BOINC Manager is attempting to communicate with the client is usually because you didn't allow the parts of BOINC through the firewall, so no "talking" between them can take place.

There are plenty of people with XP Home and Vista Home who use BOINC without any problems.

You can add users to groups in Home versions of Windows, using the net localgroup groupname username /add command on the commandline. If you want to know the ins and outs of that, look here.

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The installer didn't recommend a reboot so I didn't. I'm fine now, but I'll keep the port thing in mind if I have other problems. Thanks for the tip on the command prompt.

The installer didn't recommend a reboot so I didn't.

This was a clean install, meaning you had no previous BOINC remnants on there (in the registry at least)?

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