When I look in the change documents for this user (SUIM), i see a line withe value "Incorrect logon lock" on Tcode KRNL.
After some search on the internet, KRNL seems to be an external program, and in most of the cases, this is due to an RFC attributed to the user which includes a wrong password. I check that on RSRFCCHK, no RFC for this user.
The only clue I have is that the user had logged in BPC a few minutes before the lock, does anybody knows how can i find the error from SAP ?
I thank you in advance for your future answers, and please forgive my English

Best Regards