Why does Optimum Realism show "incompatible" or a pack format mismatch

Every resource pack declares a pack_format number in its pack.mcmeta file. Mojang bumps that number whenever the resource-pack structure changes between versions. When the number Optimum Realism declares doesn't line up with the number your Minecraft build expects, the launcher marks the pack — either with a yellow "made for a newer/older version" notice or, if the gap is bigger, by greying it out under Incompatible.

Is it safe? Yes. This is a version-label check, not a real error — the textures load and render correctly even when the numbers don't match. Click "Yes" on the prompt (on the Incompatible list, the pack still selects). It does not mean the pack is broken or that your download is corrupt.

This is different from the "Made for an older version of Minecraft" warning. That one is the friendly yellow notice on a pack that's a little behind your game. This page is specifically the pack_format number mismatch (sometimes shown as the harsher "Incompatible" state). If you landed here for the plain "older version" warning instead, see made for an older version.

To avoid it entirely: download the Optimum Realism release that matches your Minecraft version. We ship per-version builds — pick yours from the "Minecraft version" dropdown on the download page (or in your account). Not sure which release maps to your version? See which Minecraft version is it for.

If you really want to silence the label permanently, you can open pack.mcmeta in the .zip and set "pack_format" (or add a high "max_format") to match your version — but for normal play, just clicking yes is fine.