In Sql Server by default there will be one current error log file i.e. ERRORLOG and six archived log files ERRORLOG.1 (i.e. Archive #1), ERRORLOG.2 (i.e. Archive #2), …. & ERRORLOG.6 (Archive #6). Each time the Sql Server restarts, the last Archive #6 (i.e. ERRORLOG.6) is deleted, Archive #5 is moved as Archive #6 (i.e. ERRORLOG.5 -> ERRORLOG.6), Archive #4 is moved as Archive #5 (i.e. ERRORLOG.4 -> ERRORLOG.5) and So on. Current Error Log (i.e. ERRORLOG) is moved as Archive #1 (i.e. ERRORLOG -> ERRORLOG.1). And a new current error log file (i.e. ERRORLOG) is created.