Late reaction, but I've struggled with this for a while so maybe I can save somebody some time by showing my solution.
My problem showed a bit different, but the cause might be the same.
In my situation, TortoiseSVN kept on trying to connect via a proxy server. I could access SVN via chrome, firefox and IE fine.
Turns out that there is a configuration file that has a different configuration than the GUI in TortoiseSVN shows.
Mine was located here:
C:\Documents and Settings\[username]\Application Data\Subversion\
, but you can also open the file via the TortoiseSVN gui.
In my file, http-proxy-exceptions was empty
. After I specified it, everything worked fine.
[global]
http-proxy-exceptions = 10.1.1.11
http-proxy-host = 197.132.0.223
http-proxy-port = 8080
http-proxy-username = defaultusername
http-proxy-password = defaultpassword
http-compression = no