A problem just started happening to all my saved files after 3 years without ever seeing this.  When saving a V4 file and re-opening, all the injected V4 morphs are missing.  I also sometimes get the error message shown above (insufficient memory ... or the PMD file is invalid).  

I have not updated Poser 2012 or my (Mac) OS recently.  The only changes have been additions to my externally stored content library. 

Any suggestions?

There were a number of problems like this solved in PP2012 SR1. So if you are using PP2012 update it. The problem you mention is one of them

Or you can turn off external binaries off in the General preferences. This can be done for all versions of Poser