Will running two instances of solidworks at the same time cause any problems?
You will see this message ...
... for every session you open.
The only problem will be using up more computer resources resulting in lower performance, but if you have plenty of those/that you should have no problem other than the Auto recover & journal file mentioned in the warning.
If you mean that you want to run 2 different versions of SW at the one time, you should have no problems. I currently have SW2014 and SW2015 installed on my computers as I have some customers who have updated and some who have not. Make sure when you are installing the second version of SW that you install it in its own folder and that you create a new instance of toolbox. I normally install SW in folders named as per their release so SW 2014 is in a folder called SolidWorks 2014 and the toolbox folder for 2014 is in a folder called SolidWorks Data 2014 and SW2015 is installed in its related folders.
I mean two instances of the same version. Say if you wanted to have an assembly open on the left monitor and a part for that assembly on the right monitor. I know you can span the two monitors with one instance of SolidWorks, but leaves the tool bars too far away.
I save often and rarely use Auto recover, so there is nothing to worry about besides that? One of my worries was something getting crossed between the two instances and corrupting project files.
I haven't run mutliple sessions often, but when I have, I've not encountered a problem.
Also I believe if you have a part open or loaded into memory in one instance then it will only open read-only in the other instance. So if you opened the assembly first on the left monitor then when you opened the part in the right it would be read-only. So make sure you open the part first.
Let me thank everyone for their replies.
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