Finally found the source of the problem..
It appears that Hero Lab requires not just reading access, but also writing access on networks shares where portfolios are stored, in order to just opening them (I guess something is extracted in that opening process, this is probably listed somewhere in the manual already, which we IT guys always reads before using the software..
)
Anyway, in my mixed Mac/PC environment, each system has its own storage area on the network, and the Mac environment only has reading access to PC network shares and vice versa (why this, well its primary due to limit the unwanted changes made automatically by the opposite system as well as limiting the automatic creation of hidden system files etc.)
I know it sounds strange, but I am a "control freak" and it have worked very well for me for years.
Bottom line is, I found what was causing the error, and it is probably by design. I have no problem with this and I will adapt this into my way of working with Hero Lab.
However I do apologize for any inconvenience I may have caused by posting about this, especially if it is known issue, that I should have known about..
Hmmm.. I wonder why I haven't encountered this error before now though.
/Zeepee