System.UnauthorizedAccessException: Access to the registry key 'Global' is denied

Your AppFabroc client application may throw the following exception after you install a cumulative update package (CU) for AppFabric 1.1:

System.UnauthorizedAccessException: Access to the registry key 'Global' is denied.
   at Microsoft.Win32.RegistryKey.Win32Error(Int32 errorCode, String str)
   at Microsoft.Win32.RegistryKey.InternalGetValue(String name, Object defaultValue, Boolean doNotExpand, Boolean checkSecurity)
   at Microsoft.Win32.RegistryKey.GetValue(String name)
   at System.Diagnostics.PerformanceMonitor.GetData(String item)
   at System.Diagnostics.PerformanceCounterLib.GetPerformanceData(String item)
   at System.Diagnostics.PerformanceCounterLib.get_CategoryTable()
   at System.Diagnostics.PerformanceCounterLib.CategoryExists(String machine, String category)
   at System.Diagnostics.PerformanceCounterCategory.Exists(String categoryName, String machineName)
   at Microsoft.ApplicationServer.Caching.ClientPerformanceCounters.InitializeClientPerformanceCounters()
   at Microsoft.ApplicationServer.Caching.ClientPerformanceCounters.IsPerfCountersEnabled()
   at Microsoft.ApplicationServer.Caching.DataCacheFactory..ctor(DataCacheFactoryConfiguration configuration)

It is a registry permission issue. The check for performance monitor counters (ClientPerformanceCounters.IsPerfCountersEnabled) was first introduced in the CU1 release. You won't see the issue in AppFabric 1.0 and 1.1 RTM. The workaround is to add the client application account to the following groups: Performance Monitor Users group and Performance Log Users group.

As of today, these are the AppFabric 1.1 cache client versions Microsoft has released:

RTM: 1.0.4632 (29-Nov-2011)
CU1: 1.0.4639 (20-Feb-2012)
CU2: 1.0.4644 (29-May-12)
CU3: 1.0.4652.2 (27-Nov-2012)
CU4: 1.0.4653.2 (28-Mar-2013)

CU=cumulative update