Comment # 1 on bug 1006592 from Wolfgang Bauer

(In reply to David Webb from comment #0)
> I next updated the system on Saturday 22 October. When I next tried to use
> it I found that Okular will no longer display eps files - although if they
> are converted to pdf form (using ps2pdf) the pdf file displays correctly

Strange. There hasn't been an update to Okular or KDE in general in 42.1
(except a security fix for kcoreaddons that's unlikely to cause this).

There has been an update to ghostscript though, which okular uses for
displaying postscript files (via libspectre).
Can you display the file with gs?
Does reverting the ghostscript update fix the problem?

Maybe the ghostscript update broke libspectre.
Evince uses that as well AFAICS, so it may be helpful to try whether this is
affected too.