Excel question

Have standard w2k and office 2000 build on various PC’s. Svce packs appear up to date. On one PC, an xls spreadsheet does not open. Get blank “grey” page. On another PC with same specs, it opens fine.
Looks like all the settings appear the same, eg. Tools>Macro>Security set to High, but does not work even if wet to Low (on problem PC).
Under Windows>Hide … it is definitely not hidden.
Other small settings appear the same also. The xls was originally emailed…a standard proceedure for these users. The problem PC could open the emails/xls’s a few days ago…
Absolutely “baffled”!
Any help appreciated…thx in advance.