AppFabric ErrorCode<ERRCA0017><ES0006>:

I was also having this error. Just to test client in development I switched off security by using AppFabric Power Shell command

   Stop-CacheCluster
   Set-CacheClusterSecurity -SecurityMode None -ProtectionLevel None
   Start-CacheCluster

Also set following in client application in web.config

   <dataCacheClient>
     <securityProperties mode="None" protectionLevel="None"/>
   </dataCacheClient>

This is not production scenario but the above error disappear when these settings are applied.

I had a similar issue, running IIS 7.5 on Windows Server 2008 R2. I resolved it by issuing the following commands in PowerShell (started from the Windows AppFabric folder in Start, All Programs):

New-Cache -CacheName NameOfCacheAsSetInWebConfig -TimeToLive 30  
Grant-CacheAllowedClientAccount "IIS AppPool\NameOfAppPoolRunningSite"

Once I did that, I was all set.

Have you granted access to the cache for whatever user your website is running as?

Grant-CacheAllowedClientAccount Gagan