I got the system tray icon of the Beta 4 update downloading.
Then I got the notice to "click here to install update." I did. Nothing happened. I clicked it again. I got a system error dialog box. After that, the tray icon didn't respond to anything. Logos4Setup.exe was still in memory, but it didn't look like it was doing anything.
I rebooted the machine and got the error below upon rebooting. I tried to launch L4, got the install updates dialog. It ran properly. L4 says it is Beta 4 now.
