Problems saving .tiff file

I am trying to save a .psd to a .tiff file. My .psd has a couple layers and a drop shadow effect. When I save the file seems to be fine until i veiw it in any Windows or Microsoft view, thumbnail view or application such as word, it looks squeezed and totally washed out of colour and almost transparant? I have saved like this before and never encountered this problem. It seems to appear properly when opened in InDesign, Photoshop. I use these photos to send to other people who will be viewing them and using them in Microsoft applications such as PowerPoint, so I'm concerned that it won't open properly for them.
I am using Photoshop CS and Microsoft Windows Windows XP Professionl Version 2002 Service Pack 3. Any suggestions to what might be happening or what I might be doing wrong? help I have a deadline!
Thanks, Roni

Roni, Powerpoint and some othe MS programs will open a TIFF but they usually only see one layer. Those programs are not designed to handle multiple layers or opacity, or adjustment layers. These all contain prorpietary format that al of the applications in the Adobe Suite can handle, but MS apps can not.
What you can do is place a composite layer as the top layer and save the file. Regards, MM