Photo thumbnails load, then quickly disappear...HELP!

[SIcivic07]

I have encountered this problem just a few days ago and cannot find a single solution anywhere online...

On BOTH my PC hard drive (windows vista) and my external hard drive in which i use to store extra photos...the photo thumbnails will load and then within a few seconds, will disappear and the icons will be the default photo icon (blue landscape, or whatever it is)...

Why on earth does this happen? I cleared up some extra room on my PC hard drive, which solved the problem for about 12 hours, then it started happening again...i also plugged in my external today to store some more pics, and noticed that it is happening on there too!!

HELP!

 

[richc46]

Insufficient memory
Memory problems
Graphics card or driver

I think these are the most common reasons.

 

[SIcivic07]

Insufficient memory
Memory problems
Graphics card or driver

I think these are the most common reasons.

But i have now cleared up room on the PC, that works fine for now...how can we explain the external USB hard drive doing the same thing?