Reds too red

I'm new to this forum and have a problem with my 5 year old Imac.

It appears that photos imported into my Imac with the colour red appear very red indeed, too much so. The problem is noticeable in all programs, be it Iphoto, Safari, Preview, Photoshop, or Lightroom. I have calibrated the screen and I know the source photo is OK.

The strange thing is that when I email a photo the colour problem remains and the original "look" is lost. However, when I open the same photo on my Macbook running the same programs the photo is fine and does not appear too red? I have just imported a photo of my baby girl and her blondish hair is looking very orange on my Imac.

Any ideas of what could be the problem with the computer?

Many thanks for any input.

a very strange problem indeed. A program like lightroom doesn't change the original file.

So basically when you open a photo on your iMac it gets too red? If you open a perfect photo with preview and the close it and send it through mail, it is red?

It is clear that my Imac shows reds too strongly, a saturation problem? Calibrating the screen does not help.

What bothers me more though is that exported photos then appear just as bad on other computers. I have done some more experimenting and it seems that the problem lies with how I export photos from Lightroom.

If I export with file setting set as JPEG or even Export as email it seems to export with too much saturation /strong reds. The solution is to only export from lightroom with file setting set to original.

Why does Lightroom alter tones when I export as JPEG? Again, I have only noticed this on other computers as mine always show everything too red!