Most repair tools are a black box: file in, file out, no idea what changed. This one opens the Excel, Word or PowerPoint file, checks every part against ECMA-376, and shows the exact fault: the XML with a caret on it and the cell or slide it damages. It catches what AI-generated files get wrong: numbers stored as text, formulas whose saved answer is false, XLOOKUP that shows #NAME? on older Excel. No file comes back unless the Open XML SDK accepts it. Free, no account.
