Non.7z

: Delete the installer file you previously downloaded to ensure no corrupted data remains.

: If you encounter a similar error message like "Can not open file as archive" while manually using 7-Zip, it often means the file's start or end headers are damaged. Expert users sometimes use hex editors to repair these headers . Non.7z

Are you seeing this error with a like ChemDraw, or with a general file you downloaded? : Delete the installer file you previously downloaded

: Some technical sites like Yodot suggest using specific repair utilities to scan and fix the internal structure of the .7z file if redownloading doesn't work. Non.7z