Daly, and all, MSC (big hardware company) sent me their CDROM which is for windows only. They data file is called "addoc.dat" and based on the first page, that is the file I want. When I open it with Word, and save it as a "doc" file, the doc file is huge, but still cannot scroll past page 1. Daly, the freeware utility you mentioned did not work. Any other suggestions (except to buy a windows machine)? Lee Date: Tue, 11 Mar 2008 19:03:51 -0700 From: Daly Jessup <jessup at san.rr.com> Subject: Re: [X4U] Dat file extension > ...Does anybody know how to open a 200+ MB file that has a ".dat" > extension. With Word and Excel, I seem to only get the first page. > TextEdit chokes... What's the name of the file? There's a freeware utility that will open winmail.dat files. Is yours one of those? <http://www.versiontracker.com/dyn/moreinfo/macosx/8415>