Hi prk,
The name of the file that inserts the Excel export option is uxfxls.dll, and it can be found in the C:\windows\crystal (or C:\winnt\crystal) directory. Check your workstation to see if it is there, and if not, then copy it from one of the stations that does have it. Also check the file date on those stations that allow Excel exporting; the one that should be installed is 6/20/95.
We haven't run into this issue before. Is there any corrolation between the stations that are OK and those missing the export (such as installed programs, versions of NT, login scripts, etc)? It's possible that another program may have overwrote or 'upgraded' the file, making it inaccessible by Quik Reports for Windows.