My Optimum Realism download won't open or says the zip is corrupt — how do I fix it
A "corrupt" or zero-byte zip almost always means the download was interrupted or your antivirus quarantined part of it. Re-download on a stable connection, leave it zipped, and drop the whole .zip into your resourcepacks folder.
Re-download the whole file
A zip that "can't be opened" is usually a partial download — the connection dropped or it was cancelled. Delete the file and download again on a stable connection; the 256x and 512x packs are hundreds of MB to ~1.5 GB.
Check antivirus didn't quarantine it
Some antivirus tools flag large unknown zips and silently strip part of the archive, which breaks it. Open your antivirus protection history, allow the file, then re-download.
Leave it zipped
You don't extract a resource pack. If you unzipped it and re-zipped it yourself, the folder structure changes and Minecraft rejects it. Use the original .zip straight from the download.
Confirm the file size looks right
Right-click the file → Properties. A 0 KB or suspiciously small file is a failed download. Rough expected sizes: 64x ≈ 67 MB, 128x ≈ 159 MB, 256x ≈ 529 MB, 512x ≈ 1.46 GB.
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