Re: Avatar upload failed
Okay, a couple of additional questions:
You state that permissions for blog.dir is set to 777 and it is owned by your FTP account. Is the owner of your FTP account the same as the owner of your html folder? If not, that may be your problem.
The error message you listed, “Directory index forbidden by Options directive: /var/www/html/”, can indicate several things including an improper virtual host set up. Are you on a dedicated server or a shared hosting account? I would contact your ISP and ask for assistance with this particular error.
Also, with regards to that error, if you’ve customized your .htaccess file, you might have inadvertently made some changes that could cause this issue. You can always try adding:
to your .htaccess file, but that would not really help to determine why this error is being thrown in the first place. I would prefer that you get WPMU + BuddyPress functioning with the default .htaccess file.
Was WordPress Mu working without issue before installing BuddyPress?