403 Error when access Table Storage using SAS token

Question

I have Azure Mobile Service which has a custom API to generate a sas token for accessing Table Storage from Windows Store app.
I get following error in Windows Store app while accessing table storage using sas token:
Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature.
Example of sas token generated:
se=2014-09-12T03%3A10%3A00Z&sp=rw&spk=MicrosoftAccount%3A005d92ef08ec5d83081afed1e08641d2&epk=MicrosoftAccount%3A005d92ef08ec5d83081afed1e08641d2&sv=2014-02-14&tn=Folders&sig=91c7S1QM0byNdM80JncwRribXqsWS1iKmOH8cRvHWhQ%3D
Azure Mobile Services API Code that generates sas token:
exports.get = function(request, response) {
var azure = require('azure-storage');
var accountName = 'myAccountName';
var accountKey = 'myAccountKey';
var host = accountName + '.table.core.windows.net';
var tableService = azure.createTableService(accountName, accountKey, host);
var sharedAccessPolicy = {
AccessPolicy: {
Permissions: 'rw', //Read and Write permissions
Expiry: dayFromNow(1),
StartPk: request.user.userId,
EndPk: request.user.userId
var sasToken = tableService.generateSharedAccessSignature('myTableName', sharedAccessPolicy);
response.send(statusCodes.OK, { sasToken : sasToken });
function dayFromNow(days){
var result = new Date();
result.setDate(result.getDate() + days);
return result;
Windows Store app code that uses sas token:
public async Task TestSasApi()
try
var tableEndPoint = "https://myAccount.table.core.windows.net";
var sasToken = await this.MobileService.InvokeApiAsync<Azure.StorageSas>("getsastoken", System.Net.Http.HttpMethod.Get, null);
StorageCredentials storageCredentials = new StorageCredentials(sasToken);
CloudTableClient tableClient = new CloudTableClient(new Uri(tableEndPoint), storageCredentials);
var tableRef = tableClient.GetTableReference("myTableName");
TableQuery query
= new TableQuery().Where(TableQuery.GenerateFilterCondition("PartitionKey",
QueryComparisons.Equal,
this.MobileService.CurrentUser.UserId));
TableQuerySegment seg = await tableRef.ExecuteQuerySegmentedAsync(query, null);
foreach (DynamicTableEntity ent in seg)
string str = ent.ToString();
catch (Exception ex)
string msg = ex.Message;
Exception:
Any help is appreciated.
Thanks in advance!
Thanks, Vinod Shinde

Answer 1

Hi Mekh,
Thanks for the links. I checked them and mostly they are due to date time on client and server.
But this is not the case in this scenario.
here is the Request and Response from Fiddler.
Request:
GET
https://myaccount.table.core.windows.net/Folders?se=2014-09-13T02%3A33%3A26Z&sp=rw&spk=MicrosoftAccount%3A005d92ef08ec5d83081afed1e08641d2&epk=MicrosoftAccount%3A005d92ef08ec5d83081afed1e08641d2&sv=2014-02-14&tn=Folders&sig=YIwVPHb2wRShiyE2cWXV5hHg0p4FwQOGmWBHlN3%2FRO8%3D&api-version=2014-02-14&$filter=PartitionKey%20eq%20%27MicrosoftAccount%3A005d92ef08ec5d83081afed1e08641d2%27
HTTP/1.1
Accept: application/atom+xml, application/xml
Accept-Charset: UTF-8
MaxDataServiceVersion: 2.0;NetFx
x-ms-client-request-id: b5d9ab61-5cff-498f-94e9-437694e9256c
User-Agent: WA-Storage/4.2.1 (Windows Runtime)
Host: todoprime.table.core.windows.net
Response:
HTTP/1.1 403 Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature.
Content-Length: 437
Content-Type: application/xml
Server: Microsoft-HTTPAPI/2.0
x-ms-request-id: 22c0543b-0002-0049-7337-da39f4000000
Date: Thu, 11 Sep 2014 02:33:28 GMT
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<error xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">
  <code>AuthenticationFailed</code>
  <message xml:lang="en-US">Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature.
RequestId:22c0543b-0002-0049-7337-da39f4000000
Time:2014-09-11T02:33:29.6520060Z</message>
</error>
Do you see anything different in this request/response?
Thanks, Vinod Shinde