It's not really a folder - it's a control panel item: You can usually get to it by clicking the Start button and going to "Printers and Faxes" If you don't see that, open the Control Panel and go to "Printers and Faxes" from there.
You don't neccessarily need to delete the printer, and it won't neccessarily be "Intuit", although they are a common culprit...
The problem that this post was addressing is that if any Windows printers are set to use the same port (usually LPT1 or COM1) that the receipt printer is on, it will block OPOS from claiming the printer. Even if the printer is not physically connected to the computer, the Windows printer object will cause problems. Some software created a "Virtual Printer" when it is installed - some examples are Quickbooks (INTUIT), Adobe Acrobat and Microsoft Office. Some of these virtual printers get assigned a PORT - usually LPT1 or COM1 - by default. If you just go into the printer properties and look at the Ports tab, you can assign them to a different port and solve your problem without deleting the printer.
Oh, also, if you are using OPOS, you do NOT want to install the windows driver for the receipt printer OR create it as a Windows printer - that will gum up the OPOS works in the same way the virtual drivers discussed above will.
I'm not sure if this condition is directly tied to error 425, but it very well may be...
Good Luck!