For legacy versions (MAGIX and SCS era) you may install to 2 PCs and use it on 1 at a time. If you want to install it to a 3rd PC you will want to log into your account and deactivate one of the other two installs first, then install and activate to the new PC.
You may log onto your MyAccount on magix.com and deactivate the software from the previous PC, then install it to the current PC you are using it on afterward.
Go to www.vegascreativesoftware.com
Log into your MyAccount
Click MyProducts
Click "show more details" under the serial
Click "deactivate" for the PC you want to deactivate from
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