This project is read-only.

Connection problems

Oct 25, 2012 at 7:26 AM


I wrote a simple agent and tested it with MT's strategy tester. After a number (5000+) of ticks the Expert_NET advisor was no longer able to establish a connection to Gateway.exe and the neworking stack on my pc (W7 x64) seemed to be crashed. Only a restart of the network subsystem solved this issue.

I observed that for each tick a different (ascending) portnumbers are used. Is it possible that Windows runs out of available port numbers?

I think that this is a serious issue because stability is a major factor in trading agent development.


Br, Stefan.

Oct 25, 2012 at 8:25 AM

Hi Stefan,

This is serious issue. I don't have time right now to repeat your test as I under pressure to prepare new release of TradePlatform. It's actually has some improvements regarding TCP connection reliability. I will create internal work item and will have a look as soon as it become possible.

Thanks for pointing to such important topic and if you have more time, can you repeate your test case in order to make sure that problem really there and it wasn't like network accident or something.

Oct 25, 2012 at 9:36 AM

Hi Vladkalos,

Fortunately it is reproducable. Some more information:


  • Windows 7 x64 Professional SP 1
  • Intel Core i5-2520M
  • 8 GB RAM


  • MT 4.00 build 438
  • Gateway.exe

Strategy Tester settings:

  • Model: every tick, EURUSD
  • Period: M5
  • Use data from 2012.01.01 to 2012.10.01
  • Visual Mode enabled
  • Speed 32 (max)
  • Modelling quality 90%

The MT Strategy Tester journal says in case of error for each connection attempt:

"... Net Bridge Error: connect() failed: 10055"

I found no events in the Windows Event Viewer...

Oct 25, 2012 at 10:01 AM

yesterday I had something really similar ("... Net Bridge Error: connect() failed: 10055") and only restarting MT4 helped. It's nice that yours and mine issues are close. I will have a deeper look in nearest days.

Stay with us. :)

Oct 25, 2012 at 11:58 AM

Good news Stefan and everybody. I just managed to test this case and found an issue in TCP protocol handling. Fixed now and will be delivered with upcoming release. Many thanks.

Oct 29, 2012 at 11:48 AM

Issue fixed in TradePlatform.NET 2.0