Applications are not visible in RDWEB access

Sometimes applications can not be visible in Remote desktop web access. It looks that they are deployed and published correctly, you are able to connect to them via Remote app. In these cases I found mostly two different problems:
First problem
Server, that is hosting the RD Web application website, is not a member of Windows Authorization Access Group. RD Web Access server directly queries the servers and filters the retrieved list of RemoteApp programs based on the ACLs and needs permissions to do that. To solve or control this settings do the following steps:

• Open the Active Directory Users and Computers, expand the console and find the name of RD Web Access server.
• Right-click on it and select Properties, then in Member Of tab, add the Windows Authorization Access Group.

Second problem
Security settings in WMI control are not correct. Also this issue is easy to fix:

• On the server, that is hosting RD Web Access, open start menu and run WMIMGMT.MSC.
• Right-Click on WMI Control (Local) and select Properties.
• Expand Root, CIMV2 and click on TerminalServices.
• Click on Security and look for TS Web Access Computers (COMPUTERNAME TS Web Access Computers).
• If TS Web Access Computers group is not present, then add it.
• Add the Execute Methods, Enable Account and Remote Enable rights to this group.

After this check the RD Web Applications in most cases work.

Future reading: http://blogs.msdn.com/b/rds/archive/2009/06/12/introducing-remoteapp-user-assignment.aspx.