A while ago, I was working with a not so cooperative corporate firewall. All web browsers would work fine, but most other applications would not go through the proxy in a nice way.
For instance, DropBox would show the dreadfull “Connection Error” dialog shown on the right.
That dialog basically means “Dropbox has no clue what happens, try fiddling with your proxy or account settings, then press Reconnect Now” to retry.
Many other applications had issues (for instance Visual Studio connecting to Team Foundation System was very unreliable and the workarounds clumsy).
CNTLM: not the solution
I got inspired by the [WayBack] I code and code: Tutorial: How to use Dropbox behind a corporate proxy server using CNTLM, even though I was pretty sure the corporate firewall was not NTLM based.
And indeed, CNTLM -v -M http://google.com -c CNTLM.INI would give errors like this:
cntlm: Proxy returning invalid challenge!
headers_send: fd 4 warning -999 (connection closed)
Connection closed
HTTP Fiddler: looks promising
So I fired up my old buddy [WayBack] Fiddler 2 HTTP debugging proxy.
Further on, you will learn that Fiddler2 is much more, but right now it is enough to know that it basically sits as a local proxy between your applications and the outside world. Read the rest of this entry »
The Wiert Corner - irregular stream of stuff 