The Premium and the Ultimate networked licenses are cascaded, which means you simply have Inventor Pro installed on both machines, and Inventor always starts out at the lower functionality (Premium). When any Pro functionality is used, the license escalates to the higher level (Ultimate), if the Ultimate license is available.
Unfortunately, it doesn't work the opposite, so once you have escalated to the Ultimate license, you keep it until you close Inventor.
It will be a little odd with just two-- the first one to get a license gets the Premium. If #1 has not yet used any Ultimate functions when #2 signs in, then #2 gets the Ultimate license, because that's all that's left. If #1 has already used Ultimate functions, and therefore upgraded their license, then #2 signs in with Premium, because that's all that's left.
I think the talk of home install has confused the issue already...
Bottom line you have 2 licences (one for std and one for pro). You can install these on different pc's and have users use them at the same time.
BUT... if they are the same version of Inventor you cannot install both pro and standard on the same pc - you will need to choose which pc has pro and which has standard, and sadly swap between pc's as each user wants to use the pro features. This is the situation you have at the moment...
The only way to allow both pc's to use pro (but not at the same time) is to change both Inventors to a floating network licence (which will cost $$$). This will let Inventor jump between standard and pro as the pro features are needed. (but won't let both pc's access to pro at the same time). I think sbixler is explaining that with only 2 licences one pc will always grab the pro licence, so might not fix the solution anyway - you'll need to research network licences. (pc1 loads Inventor taking the std licence, leaving the pro licence on the server for pc2. If it loads pro features before pc2 takes the remaining Inventor licence it changes to pro, leaving the std licence for pc2. If pc2 loads Inventor before pc1 accesses any pro features it will grab the pro licence anyway, leaving pc1 stuck on standard. So, yes, both pc's can run pro but it could soon turn into a headache of closing down the pro version of Inventor everytime the other pc wants to use the pro features). bit of infor about licence cascading here: http://usa.autodesk.com/adsk/servlet/ps/dl/item?si
The home install is something completely different which allows you to install the same licence/version of Inventor on 2 pc's at the same time, but you're only allowed to use 1 copy of that Inventor licence at any moment. e.g. Install Inventor standard on office pc and laptop, use office pc when in office and jump onto laptop as soon as you leave the office (as long as nobody is using Inventor on your office pc while you're on the laptop).
Please mark this response as "Accept as Solution" if it answers your question - but note that the solution may not be the answer you're wanting to hear...
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Sam is exactly right in this case.
Your best bet is just to switch workstations when one person needs to use Pro.
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