Try to recover a PDF that will not open. The tool parses whatever is readable and rebuilds the file's internal structure - the cross-reference table and object tree that readers rely on to find the pages. Files damaged by an interrupted download, a failed transfer or a crash during saving are the cases most likely to come back intact.
No. Repair reconstructs the structure around the data that survived; where page content itself was lost or truncated, there is nothing to rebuild from. A partial recovery with some pages missing is a common and legitimate outcome.
Worth trying - that pattern often means a damaged cross-reference table, which is exactly what rebuilding fixes.
No. A forgotten password is not damage, and repair does not bypass encryption.
Files are uploaded over an encrypted connection and processed on CoonTool's own server, not in your browser. The working copy is deleted automatically once the job is done, and in any case within 24 hours. Nothing is stored permanently and no account is required.