On Mon, 07 Sep 2015 14:00:26 +0100, Terry Pinnell
wrote:

This occurs usually at the start of a session or after a long gap. I
double-click a JPG in Explorer and instead of loading with the usual
speed that's one of IrfanView's impressive features, it takes 10-15
secs. During this time the LED flashes on one of my external WD hard
drives.

After that, for subsequent JPGs, it's back to normal - until hours
later when it happens again. It's as if the WD unit goes to sleep and
IV has to wake it up for some reason - even though the JPG is not on
that drive.

I'm using the latest version, 4.4.0 (32 bit) on an XP PC.

Anyone seen anything similar or have any insight into the likely cause
- and a suggested possible fix please?

You're likely catching your computer when it's doing something else,
and you had to wait for it to finish. That external drive was probably
active before you clicked on the photo - just a coincidence.

File indexing was always one of the big culprits with XP, but there's
many other thing it could be doing.