A recent Windows 7 security update has affected those who use Mach3 and Mach4 with a parallel port connection. Basically, when the parallel port is used to control your machine it "takes over" the operating system and the new update does not like it, so it crashes the whole system. The following is a fix that does not require you to uninstall any updates or upgrade to an external motion controller. These are still valid options, but this is quick, easy, and should have you back up and running in no time. Here are the instructions, which I'll break down for you below:
Go into command prompt with administrator rights and paste and add the below registers.
reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride /t REG_DWORD /d 3 /f
reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverrideMask /t REG_DWORD /d 3 /f
Restart the computer for the changes to take effect.
(You do not have to change MinVmVersionForCpuBasedMitigations.)
You can follow along with these instructions at our support video here: https://youtu.be/C_O6TQhgMlA
1.) Go to your start menu and start typing 'cmd'. The command prompt (or cmd) option should appear right away. Right click and select 'Run as Administrator.' You need to be using an administrator account as well.
2.) Once you've opened the command prompt and see 'Administrator' along the top, you're almost there. Copy the first line that starts with 'reg add'. Right click in the command window and select 'Paste'. Then hit your 'enter' key.
3.) Repeat the previous step with the second line of code: copy and then paste into the command prompt window on the next line. Hit 'enter'.
4.) You should received a successful message after each line. If you see an error message regarding your access being denied, you should double check that you are logged in to an account with administrative privileges and that you are running the command prompt as an administrator (see step 1).
5.) Restart your computer.
6.) Open Mach3 and get to work.
7.) Happy CNCing!