Another Gates trick, altho other software companies do it too. Win2k is NOT backwards compatible. Either try and save via Win2k to be Win98 format or maybe there is a utillity out there that will translate it. Never heard of one but there might just be one. But some of MS's products do allow saving to previous formats.
Autocad is another one that pulls that stunt. Some sort of marketing ploy so they don't have to continue dealing with the support issues.
When you lay out 12k or more for a software (autocad) and they 'discontinue' support within a year or two it reallllly sux.