Quick answer: check the match before reinstalling.
Verity Mod failures usually come from a compatibility mismatch rather than a damaged game. Work from the basic checks to the project-specific notes; do not randomly switch launchers or download replacement files from mirrors.
Fixes in the right order
- Wrong edition: confirm Java versus Bedrock/PE.
- Wrong game version: the mod/add-on must match your exact Minecraft build.
- Wrong loader: Java projects require the loader named by that release.
- Missing dependency: check every required library on the source page.
- Pack not enabled: Bedrock needs its stated behavior/resource packs and sometimes experiments.
- Modpack conflict: try the project alone in a new profile or world.
Useful information for a support request
Share the project link, author, project ID, game version, loader, exact file name, dependency versions, platform, and the first visible error. “It does not work” is too little information to reproduce the problem.
Symptom-to-cause table
Start from what you actually see
What not to do
Do not solve a mismatch by downloading another same-name file from a mirror. That changes too many variables at once and can move you further away from the project the tutorial describes.
The Bedrock-specific symptom notes above are derived from the current public descriptions of the two named Bedrock projects. They do not diagnose every project with “Verity” in its title.