Viewing JPG's in LR vs. Other Photo Viewers

I finished processing a photo within LightRoom, converted to JPG and it looked great. Sent it to the client and they were less happy with it.

I finally realized they were viewing the photo using MS Picture Manager and I view via LR. The JPG looked great in LR..just as it looked when I converted. Within MS Picture Manager however, it is much more orange looking and was unacceptable.

Why is this? ...and what advice from does anyone have as to sharing sending out proofs of your work to clients and ensure they are seeing the photo's you intend.

thanks

Convert an image to sRGB before mailing or putting on the web.
Read the link from my sig.
If the client has a badly adjusted display, there's nothing you can do...