There are two ways to run multiple mIRC instances with separate settings:
1. Install a copy of mIRC for each separate set of settings you want. After installation go to the folder you installed mIRC to and create a blank file called mirc.ini. Now when you run that copy of mIRC it will store all settings inside its installation folder just like versions of mIRC before 6.3.
2. Install mIRC once. Create a different shortcut for each set of settings you want. For each shortcut use the -r<pathname> switch to set a different folder for mIRC to store its settings in. Each shortcut can then be run and will have its own independent settings stored in the location you provided.
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