# panic: proto: file "service.proto" is already registered

- **ID:** `go/grpc-protobuf-version-mismatch`
- **Domain:** go
- **Category:** build_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The same .proto file is compiled into multiple packages, causing double registration at init time.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.4 | active | — | — |

## Workarounds

1. **** (90% success)
   ```
   Check go.mod for duplicate dependencies and use replace directives to unify versions.
   ```
2. **** (50% success)
   ```
   proto.RegisterFile("custom_service.proto", fileDescriptor)
   ```

## Dead Ends

- **** — Regeneration will still produce the same conflict if imports are duplicated. (80% fail)
- **** — Renaming the package doesn't resolve the file registration conflict. (60% fail)