# setOpenedAt

Set opened time for a specific mail. This method can only be performed by the receiver of the mail.

### Usage

```ts
const mailIndex = 1n;
const txResponse = await mail.setOpenedAt(mailIndex);
```

### Returns

`Promise<EthereumTransactionResponse>`

A promise that resolves to the response from the `sendTransaction` method on the `walletClient` provided by the developer on `Mail` initialization.

### Parameters

#### mailIndex

* **Type** `bigint`

The index of the mail for which the opened time needs to be set.