# go: module github.com/foo/bar@v1.2.3: reading https://proxy.golang.org/github.com/foo/bar/@v/v1.2.3.mod: 404 Not Found

- **ID:** `go/module-not-found-reading-https-proxy`
- **Domain:** go
- **Category:** module_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The module version does not exist on the configured proxy or the module path is wrong/mis-cased. Go module paths are case-sensitive and require the exact tag (e.g. v1.2.3, not v1.2).

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.16+ | active | — | — |
| 1.21+ | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   git ls-remote --tags https://github.com/foo/bar | grep v1.2.3
go get github.com/foo/bar@v1.2.3
   ```
2. **** (90% success)
   ```
   GOPRIVATE=github.com/foo/* GONOSUMDB=github.com/foo/* GOPROXY=direct go get github.com/foo/bar@v1.2.3
   ```
3. **** (80% success)
   ```
   go get github.com/foo/bar@<commit-sha>
   ```

## Dead Ends

- **** — go still needs to resolve the original module graph and reports 'replacement directory does not exist' (70% fail)
- **** — clearing cache does not create a missing version on the proxy (85% fail)
- **** — does not change remote availability of the module version (90% fail)