Update Alias

Associates an email address as an alias for another user.


  • In order to successfully use this endpoint the logged in user must be a Mimecast administrator with at least the Directories | Groups | Edit permission.


To use this endpoint you send a POST request to:

  • /api/user/update-alias

Request Headers

The following request headers must be included in your request:

Authorization Please see the Authorization guide for more information on building the Authorization header.

A randomly generated GUID, for example,

x-mc-app-id The Application ID provided with your Registered API Application.

The current date and time in the following format, for example,

Tue, 24 Nov 2015 12:50:11 UTC

Request Body

 "data": [
         "aliasFor": "String",
         "alias": "String"
aliasFor String Required The primary email address to set the alias for.
alias String Required The email address to set as an alias address.


 "fail": [], 
 "meta": {
  "status": Number
 "data": [
   "domain": "String", 
   "isInternal": Boolean, 
   "alias": "String", 
   "aliasDisplayName": "String", 
   "aliasFor": "String", 
   "type": "String"
meta object
status Number The function level status of the request.
data array
domain String The domain of the alias address.
isInternal Boolean If the alias is internal (true) or external (false).
alias String The alias email address.
aliasDisplayName String The display name of the alias address.
aliasFor String The primary email address that the alias was associated to.
type String The Mimecast address type of the alias address.
fail array

When a request is successful the fail array will be empty.

errors Array of error objects An array of error objects describing the error returned from the API.

errors object

message String The error message.
code String The Mimecast code associated with the error.
retryable Boolean If the error is retryable

Sample Code

Sample code is provided to demonstrate how to use the API and is not representative of a production application. To use the sample code; complete the required variables as described, populate the desired values in the request body, and execute in your favorite IDE.  Please see the Global Base URL's page to find the correct base URL to use for your account.

POST {base_url}/api/user/update-alias
Authorization: MC {accesskKey}:{Base64 encoded signed Data To Sign}
x-mc-date: {dateTime}
x-mc-req-id: {unique id}
x-mc-app-id: {applicationId}
Content-Type: application/json
Accept: application/json

 "data": [
         "aliasFor": "String",
         "alias": "String"
import base64
import hashlib
import hmac
import uuid
import datetime
import requests

# Setup required variables
base_url = "https://xx-api.mimecast.com"
uri = "/api/user/update-alias"
url = base_url + uri
access_key = "YOUR ACCESS KEY"
secret_key = "YOUR SECRET KEY"

# Generate request header values
request_id = str(uuid.uuid4())
hdr_date = datetime.datetime.utcnow().strftime("%a, %d %b %Y %H:%M:%S") + " UTC"

# Create the HMAC SHA1 of the Base64 decoded secret key for the Authorization header
hmac_sha1 = hmac.new(secret_key.decode("base64"), ':'.join([hdr_date, request_id, uri, app_key]),

# Use the HMAC SHA1 value to sign the hdrDate + ":" requestId + ":" + URI + ":" + appkey
sig = base64.encodestring(hmac_sha1).rstrip()

# Create request headers
headers = {
    'Authorization': 'MC ' + access_key + ':' + sig,
    'x-mc-app-id': app_id,
    'x-mc-date': hdr_date,
    'x-mc-req-id': request_id,
    'Content-Type': 'application/json'

payload = {
 "data": [
         "aliasFor": "String",
         "alias": "String"

r = requests.post(url=url, headers=headers, data=str(payload))

print r.text
static void Main(string[] args)
            //Setup required variables
            string baseUrl = "https://xx-api.mimecast.com";
            string uri = "/api/user/update-alias";
            string accessKey = "YOUR ACCESS KEY";
            string secretKey = "YOUR SECRET KEY";
            string appId = "YOUR APPLICATION ID";
            string appKey = "YOUR APPLICATION KEY";

            //Generate request header values
            string hdrDate = System.DateTime.Now.ToUniversalTime().ToString("R");
            string requestId = System.Guid.NewGuid().ToString();

            //Create the HMAC SHA1 of the Base64 decoded secret key for the Authorization header
            System.Security.Cryptography.HMAC h = new System.Security.Cryptography.HMACSHA1(System.Convert.FromBase64String(secretKey));

            //Use the HMAC SHA1 value to sign the hdrDate + ":" requestId + ":" + URI + ":" + appkey
            byte[] hash = h.ComputeHash(System.Text.Encoding.Default.GetBytes(hdrDate + ":" + requestId + ":" + uri + ":" + appKey));

            //Build the signature to be included in the Authorization header in your request
            string signature = "MC " + accessKey + ":" + System.Convert.ToBase64String(hash);

            //Build Request
            System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(baseUrl + uri);
            request.Method = "POST";
            request.ContentType = "application/json";

            //Add Headers
            request.Headers[System.Net.HttpRequestHeader.Authorization] = signature;
            request.Headers.Add("x-mc-date", hdrDate);
            request.Headers.Add("x-mc-req-id", requestId);
            request.Headers.Add("x-mc-app-id", appId);

            //Add request body
            //Create and write data to stream
            string postData = @"{
                 ""data"": [
                         ""aliasFor"": ""String"",
                         ""alias"": ""String""

            byte[] payload = System.Text.Encoding.UTF8.GetBytes(postData);

            System.IO.Stream stream = request.GetRequestStream();
            stream.Write(payload, 0, payload.Length);

            //Send Request
            System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();

            //Output response to console
            System.IO.StreamReader reader = new System.IO.StreamReader(response.GetResponseStream());
            string responseBody = "";
            string temp = null;
            while ((temp = reader.ReadLine()) != null)
                responseBody += temp;
#Setup required variables
$baseUrl = "https://xx-api.mimecast.com"
$uri = "/api/user/update-alias"
$url = $baseUrl + $uri
$accessKey = "YOUR ACCESS KEY"
$secretKey = "YOUR SECRET KEY"

#Generate request header values
$hdrDate = (Get-Date).ToUniversalTime().ToString("ddd, dd MMM yyyy HH:mm:ss UTC")
$requestId = [guid]::NewGuid().guid

#Create the HMAC SHA1 of the Base64 decoded secret key for the Authorization header
$sha = New-Object System.Security.Cryptography.HMACSHA1
$sha.key = [Convert]::FromBase64String($secretKey)
$sig = $sha.ComputeHash([Text.Encoding]::UTF8.GetBytes($hdrDate + ":" + $requestId + ":" + $uri + ":" + $appKey))
$sig = [Convert]::ToBase64String($sig)

#Create Headers
$headers = @{"Authorization" = "MC " + $accessKey + ":" + $sig;
                "x-mc-date" = $hdrDate;
                "x-mc-app-id" = $appId;
                "x-mc-req-id" = $requestId;
                "Content-Type" = "application/json"}

#Create post body
$postBody = "{
                 ""data"": [
                         ""aliasFor"": ""String"",
                         ""alias"": ""String""

#Send Request
$response = Invoke-RestMethod -Method Post -Headers $headers -Body $postBody -Uri $url

#Print the response
public static void main(String[] args) throws java.io.IOException, java.security.NoSuchAlgorithmException, java.security.InvalidKeyException {

        //set up variables for request
        String baseUrl = "https://xx-api.mimecast.com";
        String uri = "/api/user/update-alias";
        String url = "https://" + baseUrl + uri;
        String accessKey = "YOUR ACCESS KEY";
        String secretKey = "YOUR SECRET KEY";
        String appId = "YOUR APPLICATION ID";
        String appKey = "YOUR APPLICATION KEY";

        //create URL object
        java.net.URL obj = new java.net.URL(url);

        // set guid for x-mc-req-id header
        String guid = java.util.UUID.randomUUID().toString();

        // set date for x-mc-date header
        java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss z");
        String date = sdf.format(new java.util.Date());

        //create signature for the Authorization header
        String dataToSign = date + ":" + guid + ":" + uri + ":" + appKey;
        String hmacSHA1 = "HmacSHA1";
        javax.crypto.spec.SecretKeySpec signingKey = new javax.crypto.spec.SecretKeySpec(org.apache.commons.codec.binary.Base64.decodeBase64(secretKey.getBytes()), hmacSHA1);
        javax.crypto.Mac mac = javax.crypto.Mac.getInstance(hmacSHA1);
        String sig = new String(org.apache.commons.codec.binary.Base64.encodeBase64(mac.doFinal(dataToSign.getBytes())));

        // create request object
        javax.net.ssl.HttpsURLConnection con = (javax.net.ssl.HttpsURLConnection) obj.openConnection();

        //set request type to POST

        //add reuqest headers
        con.setRequestProperty("Authorization", "MC " + accessKey + ":" + sig);
        con.setRequestProperty("x-mc-req-id", guid);
        con.setRequestProperty("x-mc-app-id", appId);
        con.setRequestProperty("x-mc-date", date);
        con.setRequestProperty("Content-Type", "application/json");
        con.setRequestProperty("Accept", "application/json");

        //Add post body to the request
        String postBody = "{\n" +
                " \"data\": [\n" +
                "     {\n" +
                "         \"aliasFor\": \"String\",\n" +
                "         \"alias\": \"String\"\n" +
                "     }\n" +
                " ]\n" +
        java.io.OutputStream os = con.getOutputStream();

        //process response
        java.io.BufferedReader in = new java.io.BufferedReader(
                new java.io.InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuffer response = new StringBuffer();

        while ((inputLine = in.readLine()) != null) {

        //return result