Why we can not use System’s PC for Excel or ward or LIMS usage…???
You should not use PC system as such unless it is properly qualified and validated. Excel sheets must validated before use. Similarly, it’s compliance to 21 CFR part 11 should be ensured and documented.
As per 21 CFR , You never used Unvalidated excel sheets for calculation,
Excel sheet should be validated before it process a gxp data inc. analysis, count, or other function. And in parralel you have to protect all cells including math formula.