I didn't realise that since Adobe ended all support for Flash that it affects some users of Poser in a significant way.
Apparently Poser 7 to Poser 2014 are affected because, there, the Poser libraries are built with Flash technology included into it. In seems that, in those versions of Poser, the content library stopped working.
According to Poser Software, there are SUGGESTED SOLUTIONS to that problem. Because links to 'pay' websites are not permitted here, I cannot post the link to Poser Software's website... but you can 'Google' the following topic to search for it:
"How to fix your Runtime now that Adobe Flash has reached end of life"
If you are affected regarding this, I hope that one of the suggested solutions on their web page works for you .