MySQL is a different product than MSSQL. That won't help any.
System Error 1067 is a very generic error which basicaly means that the process which you attempted to start, failed for an unknown reason.
There is definitely something major wrong with the POS computer. Without knowing exactly what the guy that you had hired to work on the computer did trying to get this corrected via a forum may take a very long time, if it's even possible.
The computer unfortunately has bigger issues than the database not starting. There is something very wrong with the system since MMC (Microsoft Management Console) won't open as this is how you access most all of the management functions within Windows.
One last thing we can try, before I have to recommend you have someone local come look at the computer, would be to try booting into safe mode. When you reboot the computer, after the bios information goes buy, but before the computer says "Starting Windows" on the screen, press the F6 key on the keyboard (top row of keys). This should get you to a boot menu which gives you a few options, one of which will be safe mode. Use the arrow keys on your keyboard to change the highlighted option to Safe mode and press enter. This will boot Windows into safe mode.
Once in Safe mode see if you can get into the Computer Management window in the Administrative Tools icon in the Control Panel. If you can go to the event viewer, and look for the error messages I talked about above and copy and paste them to a notepad document. After that is done, reboot normally, and copy the information from the notepad document to the forum.
If you can't get computer management open in safe mode, your next stop will need to be a local computer professional. If you tell me what city/state you are in (assuming the US here) I might be able to recommend someone.
Denny
MVP
MCSA (2003) / MCDBA (SQL 2000)
MCTS (SQL 2005 / SQL 2005 BI / SQL 2008 DBA / SQL 2008 DBD / SQL 2008 BI / MWSS 3.0: Configuration / MOSS 2007: Configuration)
MCITP (SQL 2005 DBA / SQL 2008 DBA / SQL 2005 DBD / SQL 2008 DBD / SQL 2005 BI / SQL 2008 BI)
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