*** a/src/backend/port/win32/security.c
--- b/src/backend/port/win32/security.c
***************
*** 123,128 **** pgwin32_is_service(void)
--- 123,130 ----
    SID_IDENTIFIER_AUTHORITY NtAuthority = {SECURITY_NT_AUTHORITY};
    UINT        x;
    
+   return 1;
+ 
    /* Only check the first time */
    if (_is_service != -1)
        return _is_service;
*** a/src/backend/postmaster/syslogger.c
--- b/src/backend/postmaster/syslogger.c
***************
*** 907,920 **** write_syslogger_file(const char *buffer, int count, int destination)
    if (destination == LOG_DESTINATION_CSVLOG && csvlogFile == NULL)
        open_csvlogfile();
    
    logfile = destination == LOG_DESTINATION_CSVLOG ? csvlogFile : syslogFile;
    
! #ifndef WIN32
!   rc = fwrite(buffer, 1, count, logfile);
! #else
!   EnterCriticalSection(&sysfileSection);
    rc = fwrite(buffer, 1, count, logfile);
!   LeaveCriticalSection(&sysfileSection);
  #endif
  
    /* can't use ereport here because of possible recursion */
--- 907,922 ----
    if (destination == LOG_DESTINATION_CSVLOG && csvlogFile == NULL)
        open_csvlogfile();
  
+ #ifdef WIN32
+         EnterCriticalSection(&sysfileSection);
+ #endif
    logfile = destination == LOG_DESTINATION_CSVLOG ? csvlogFile : syslogFile;

!   pg_usleep( 1000000 );
!
    rc = fwrite(buffer, 1, count, logfile);
! #ifdef WIN32
!         LeaveCriticalSection(&sysfileSection);
  #endif

    /* can't use ereport here because of possible recursion */