Here is the situation and the problem:
I support an office of lawyers. (No, this is NOT the problem...)
In the course of their work, they are provided with .eml files that are exports of email messages thagt are related to their case. Sometimes these are evidence, sometimes they are supporting documents and so on. The important thing is that these are .eml files that were properly prepared.
Of course, they have e-mail open all day. When I have outlook 2013 open, and I want to also open an email message of the type described above in order to read it as part of their preparatory work, Outlook says "You cannot have two copies of Outlook running at the same time, You must close your copy of outlook before opening it again.' (or something to that effect.
In essence it seems that if Outlook is open, it tries to spawn a new running copy of the program as opposed simply opening the message in a new window. If you open, for example, Excel, and then open another spreadsheet, it does not try to reopen Excel, it opens the file in the current running copy of excel.. this does not appear to be the default behavior for Outlook.
It's really annoying to have to close outlook, double click on the EML file, then when done, close outlook, and re-open it...