Unrecognized Username Or Password

[dusanick]

I am running parallel sessions of TWS on live and paper account, for the start I utilize IBC via Task scheduler. TWS is set to run continuously with auto-restart at specific time during the day. My Live account seems to we working OK without any errors. However my paper trading sessions looses connection every day around the same time. I have tried to analyze this before as it collided with IBKR short maintenance windows early in the morning. Support asked me to upgrade to newer stable version (from 10.37.1.j to 10.37.1.o), which did not solve the problem.

Following error message:

I am attaching logs from both live and paper environment in case there are some discrepancies.
The problem in paper environment starts at 2026-01-25 06:48:34:927. When I come to the machine, the data connection is already lost and error message active. The way I need to resolve the problem is usually to exit IBC paper mode and restarting the session again. This repeats daily.
Unfortunately I cannot decipher the logs to resolve the issue. Would you be so kind and support me ? I will happily provide additional answers.

IBC-3.23.0_TWS-1037_FRIDAY_LIVE.txt
IBC-3.23.0_TWS-1037_SATURDAY_PAPER.txt

[rlktradewright]

Looking at the logfile, it certainly looks like you've got everything set up correctly.

This situation where the 'Re-login is required' dialog is displayed, followed by the 'Unrecognized Username or Password' dialogue, occurs when the user's login credentials have been invalidated by IBKR. This has been reported occasionally over the past year or two, but ti doesn't seem to affect most IBC users.

One specific cause of this was discovered a few days ago; the user was running a free trial account, rather than the paper trading account that comes with a funded llive account. Free trial accounts are actually paper trading accounts: they use the paper trading system, get free delayed market data, and have a large virtual funding,, but it seems that they may not be permitted to use auto-restart.

So can you confirm whether you are using the paper trading account that's provided with your live account, or a free trial account?

[dusanick]

Hi there, thanks a lot for looking into the log! Yea, I am using paper account together with my live funded account. What I find strange is that the behavior is specific only to paper account. I was unsure if my config for paper had any holes, but it seems its fine as well. I will make sure I will get in touch with support again. Any idea that I might try out before I do that ? I thought of having a second instance of TWS in a separate folder but I just have strong feeling this comes from IBKR directly and it won´t help me.

What I should also mention is that I am using two machines, one is on 24/7 to run my automation, second one is mainly research computer. All of my work stuff is saved on cloud and both machines have access to the files. IBC is installed on both machines separately, and I use IBC for connections to TWS from both machines.

[rlktradewright]

I think it would be worth running both IBC/TWSs on the same computer. This is the expected 'standard' way of setting things up.

Although you can run instances of TWS or Gateway on different mahcnines logged into live and paper accounts ate the same time, market data cannot be shared between machines, so only one of them will received market data. Whether that fact has any bearing on your problem I can't say without some experimenting, which I can't do just now (it's dinner time!...).

This restriction on market data being only received by one machine at a time is a hard-and-fast rule imposed by the data providers, and cannot be bypassed.

So I encourage you to try this setup.