# Error Handling Reference

Common issues and solutions:

**API Rate Limit Exceeded**
- Error: Too many requests to crypto data API
- Solution: Implement request throttling; use caching for frequently accessed data; upgrade API tier if needed

**Blockchain RPC Errors**
- Error: Cannot connect to blockchain node or timeout
- Solution: Switch to backup RPC endpoint; verify network connectivity; check if node is synced

**Invalid Address or Transaction**
- Error: Blockchain address format invalid or transaction not found
- Solution: Validate address checksums; verify network (mainnet vs testnet); allow time for transaction confirmation

**Exchange API Authentication Failed**
- Error: Invalid API key or signature mismatch
- Solution: Regenerate API keys; verify permissions (read/trade); check system clock synchronization for signatures