The 'AutoRecovery save of .pptx' produced after a crash won't open, demands a repair, or crashes PowerPoint when repairing.

What's actually wrong

After PowerPoint or your machine crashes, the Document Recovery pane offers an 'AutoRecovery save' — but that snapshot was often being written at the very moment of the crash, so it can be truncated mid-write and itself refuse to open. Frustrating but important context: the AutoRecover copy and your last manually-saved file are separate things, and often at least one of the two is intact. Recovery odds from a truncated snapshot depend on how much of the package was flushed to disk before the crash.

Free fixes — try these first

1. First try the built-in path: File > Open > Recover Unsaved Presentations (button at the bottom of the recent-files list), or File > Info > Manage Presentation — sometimes a second, older snapshot sits behind the broken one.
2. Browse the AutoRecover folder yourself: paste %AppData%\Microsoft\PowerPoint into the Explorer address bar. Copy everything you find ('AutoRecovery save of...', .pptx, .tmp) to your Desktop before reopening PowerPoint — PowerPoint cleans this folder up when it closes normally.
3. Rename any recovered .tmp file to .pptx and open it via File > Open > Open and Repair rather than double-clicking.
4. Try the snapshot in LibreOffice Impress or upload it to Google Slides — both tolerate truncated packages better than PowerPoint and may load everything up to the point the write stopped.
5. If the deck ever lived in OneDrive or SharePoint with AutoSave on, skip the local snapshot entirely: open Version history on the website and restore the last good version.

If the free fixes fail

A snapshot cut off mid-write has a broken ZIP tail, which makes PowerPoint's repair crash even though most slide data is physically present in the file. Our analyzer reconstructs the archive up to the truncation point and shows an honest percent-recovered preview — so you know whether the snapshot beats your last manual save before you spend anything.