EIP-1193 Error 4100: Unauthorized Account Race Condition Fix
EIP-1193 error 4100 "Unauthorized" is returned when an EVM web3 application attempts to invoke an account-restricted method (such as eth_sendTransaction or personal_sign) without possessing active authorization from the user. This occurs when a dApp executes requests before eth_requestAccounts has completed its handshake, or when the user changes active accounts in their browser wallet extension without the frontend dApp synchronizing its internal state. Refresh the webpage or trigger a clean reconnection to resolve the permission mismatch.
# Root Cause & Technical Architecture
The EIP-1193 provider specification defines `4100` as `Unauthorized: The requested method and/or account has not been authorized by the user.` Under EIP-2255 wallet permissions, a dApp only holds authority to interact with accounts explicitly selected by the user. If the dApp maintains a hardcoded address in state while the user switched to Account 2, calls targeting Account 1 are rejected with `4100`.
# 4-Step Actionable Diagnostic Protocol
Step-by-Step ResolutionEnsure eth_requestAccounts Precedes Transaction Calls
Never call eth_sendTransaction or personal_sign without first verifying that eth_accounts or eth_requestAccounts returns an active authorized address.
Listen to accountsChanged Events in Provider
Subscribe to window.ethereum.on("accountsChanged", (accounts) => ...) to update frontend state immediately whenever the user switches accounts.
Clear Stale dApp Connection in Wallet Settings
Open MetaMask > Connected Sites, disconnect the current website, refresh the page, and initiate a clean reconnect.
Handle Wagmi/Viem Reconnect Race Conditions
Ensure your app waits for Wagmi's useAccount() isConnected and isReconnecting flags before attempting automated signing workflows.
# Diagnostic Verification Code / Command
typescript// Subscribe to EIP-1193 accountsChanged to prevent Error 4100
if (window.ethereum) {
window.ethereum.on('accountsChanged', (accounts: string[]) => {
if (accounts.length === 0) {
console.warn('User disconnected wallet');
resetAppState();
} else {
console.log('Active account changed to:', accounts[0]);
updateCurrentSigner(accounts[0]);
}
});
}Launch WebAuthn Passkey Debugger
Execute client-side cryptographic simulation and parameter checks safely in your browser via native WebCrypto without sending private keys or mnemonics over the wire.
Read Full Investigation & Recovery Workflow
Explore complete architectural diagrams, edge-case failure trees, and detailed post-mortem analysis in our verified deep guide.
# Related Diagnostic Codes in EVM & JSON-RPC
Related Hex StatusesJSON-RPC Error -32000: Insufficient Funds for Gas * Price + Value
Fix JSON-RPC error -32000 insufficient funds for gas * price + value. Resolve native token balance shortages, fee estimation surges, and gas caps.
JSON-RPC Error -32000: Replacement Transaction Underpriced Fix
Fix JSON-RPC error -32000 replacement transaction underpriced. Apply mandatory 10%+ maxPriorityFeePerGas bump on same nonce to replace stuck mempool txs.
JSON-RPC Error -32000: Nonce Too Low Stale Wallet State Fix
Fix JSON-RPC error -32000 nonce too low. Troubleshoot stale local wallet nonce caches, pending mempool transactions, and reset account state.
# Frequently Asked Questions
FAQ SchemaWhy did I get error 4100 after switching accounts in MetaMask?
The dApp was still attempting to use your previous account address. Refresh the webpage or listen to the accountsChanged event to synchronize state.
Does eth_accounts prompt the user for permission?
No. eth_accounts returns currently connected accounts silently. To prompt the user to connect, you must call eth_requestAccounts.
Can error 4100 happen with hardware wallets?
Yes, if you switch between Ledger accounts in MetaMask without granting the dApp permission to view the newly selected hardware account.