>I am able to start and stop database after logging as user postgres in NT. It is clear that you can start and stop postgreSQL using the postgres user. Therefore access to pg_ctl.exe is working as expected! The fact that the problem only exists when you introduce a thrid party tool to perform the same tasks you are able to do when logged on as the postgres user strongly suggests that the problem is with your thrid party tool. That is your third party tool is emulating the command shell environment but not 100%. What happens when you try and run some other application using the postgres user when logged on as the postgres user? For example: 1) log on as postgres and run the program ipconfig.exe (this system program uses the kernel32.dll). 2) When you have established that the previous step works ok, run the same command from a batch/script file using the "runasv" program. Regards Donald Fraser Ps. Please do not include email addresses in your reply - they become public domian and allow spam engines to find them!