I used to have MS Picture and Fax Viewer defined as default viewer for
misc. graphic formats (e.g. .bmp, .gif, etc.).
Since a week or so, whenever I double click (i.e. open) such a file,
Picture and Fax viewer starts up and displays "Generating Preview" but
then after a few seconds the window silently disappears again without
ever showing the image. No error popup, no event log entry, nothing.

At first I thought I had a few corrupted images at hand that simply
cause the viewer to crash, but all other suitable apps at hand (paint,
PaintShop Pro, Adobe PhotShop, etc.) had absolutely no problem with
these images. Experimenting further I found that the P&F Viewer seems to
have trouble with ALL images and does not display ANY image any more! So
I rather guess, that either the application itselft is corrupted or some
config is damaged.

The only thing that comes to my mind was, that I had the shimgvw.dll
de-registered due to the wmf bug that was discovered a few months back,
but later re-registered it again after MS claimed to have fixed the
issue (and after installing the corresponding fix of course). And - at
least if I recall correct - it HAD worked again after re-registering it!

Any idea, what could cause these silent disappearance of Picture and Fax
viewer?

Michael