The customer has BMS windows server, if he Log to the DSLAM from the DOS prompet, Log successed.
If he try to log to the DSLAM from BMS platform, it fails.
BMS version is V200R011C02B026.
From SysMonitor, start the Device access Proxy Process and make it Automatic to start by default every time the BMS server restarts.
Device access Proxy Process was disabled, which is responsible for the log process.