SD-ERR-140: Could not acquire login lock
Last updated 30 July 2026
SD-ERR-140: Could not acquire login lock
This message comes from AutoTrader Web, not from your broker, and it is temporary. Before logging in to an account we take a login lock for it, so only one login runs for that account at a time. When your broker's server is slow to answer, the earlier request is still running and holding that lock, so the new login cannot start and eventually gives up with this message. Nothing is wrong with your login id, MPIN, password, API key or TOTP key. The fix is to retry: go to Accounts -> Trading Accounts, select the account and click Validate All, and it normally goes through once the broker responds again. The value in the square brackets, such as [ABJP1023 | Angel | ABJP1023], is your own account — the nickname, the broker and the login id. It is NOT a broker error code, so please do not send it to your broker's support as one.
When this happens
- 1 Your broker's server was slow to respond, so an earlier request for the same account was still running and holding the login lock.
- 2 Several actions were started on the same account at almost the same time, so a later one could not get the lock before giving up.
This message is ours, not your broker’s
Any code beginning with SD- is generated by AutoTrader Web. SD-ERR-140 is our code for “could not acquire login lock”. Your broker did not send it, and it is not a broker error code.
The value in brackets is your account, not an error code
The message ends with something like:
SD-ERR-140: Could not acquire login lock: [[ABJP1023 | Angel | ABJP1023]]Those three parts are simply your account nickname, your broker, and your login id — that is how we identify an account in our messages. In the example above, ABJP1023 is the account, not an error.
Please do not report that value to your broker’s support as an error code. They will not recognise it, and it will not get you anywhere. There is nothing for your broker to look up here.
Why it happens
Before logging in to an account, AutoTrader Web takes a login lock for it. This makes sure only one login runs for that account at a time, which keeps the session consistent and avoids hitting your broker with duplicate login requests.
When your broker’s server is slow to answer, the earlier request is still running and still holding that lock. The new login waits for its turn, and if the broker has still not responded by the time the wait runs out, it gives up and you see this message.
So the delay is at your broker’s end. Nothing is wrong with your login id, MPIN, password, API key or TOTP key — none of those need changing.
The fix: retry
- Go to the menu (Accounts → Trading Accounts).
- Select the account.
- Click Validate All.
Once your broker’s server responds normally, the lock is free and the login goes through. If it fails again, wait a short while and retry — a slow broker server usually recovers on its own.
If it keeps happening
If the same account keeps failing this way over a longer period, your broker may be having a wider problem. See What to do when one of the brokers has a problem, and contact us with your login id and the exact message if you would like us to check it.
Not the same as the trading lock
A similar message, “Could not acquire trading lock”, is about placing or reading orders rather than logging in. The cause and the fix are the same kind of thing — see Could not acquire trading lock.
