Try not to save the file or save 2nd version so your original is NOT change
--- exit and reboot.

Try compress again and if nothing happen --- do System Restore and go
back dated when your PC & PPT are good.

What PPT version you uses?  Good luck,  --Rino

I am having difficulty compressing my picture files. I right click on the
picture, choose compress and to compress for a screen (all pictures).
However, when I click apply, nothing is happening.

What can I do to bring back the compression function. It is causing my file
to be too large and I have never had this problem before.

Are the pics jpegs?

If not cut & paste special (as jpeg)

Hi,

On top of the other information you have been given, there is another
possibility. If images do not need compression, or have been compressed
before, using this feature will produce the behaviour you are seeing. I have
one here. First time I compress it, it works away hammering images smaller.
Second time, nothing happens. Could be normal behaviour. :-)

If not, also try Detect and Repair. I had a look and it appears that image
compression is installed by default, so you can't add it as a feature.... it
should be there and should work.