rdesktop A Remote Desktop Protocol Client for accessing Windows NT Terminal Server.
Jacco's rdesktop page for the OS/2 port and links to other rdesktop.
properJavaRDP Java based RDP client based on rdesktop.
Elusiva - Open Source JavaRDP Java based RDP client based on rdesktop and properJavaRDP.
Lixia-JavaRDP GNU GPL v3 licensed Java RDP client for Windows Terminal Services based on properJavaRDP.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license.

Licensing

Server 2008
Microsoft - Licensing Remote Desktop Services in Windows Server 2008 R2

Server 2003
Brian Madden - The Ultimate Guide to Windows 2003 Terminal Server Licensing see deze link for the PDF version.
Microsoft - Windows Server 2003 Terminal Server Licensing contains a link to a Word document of the same name.
Microsoft - Licensing Terminal Server in Windows Server 2003 R2
Microsoft - Windows Server 2003 Pricing and Licensing: Frequently Asked Questions
Microsoft Support - The function of Terminal Server CALs in Windows Server 2003 (KB822134)
Microsoft Support - Removing Terminal Server licenses from an RDP client (KB187614)

Printer Redirection

Microsoft Support - Windows 2000 or Windows Server 2003 Terminal Services server logs events 1111, 1105, and 1106 (KB239088)
Microsoft Support - Printers that use ports that do not begin with COM, LPT, or USB are not redirected in a remote desktop or a terminal services session (KB302361)
Microsoft TechNet - Event ID 1111 — Terminal Services Printer Redirection describes the steps for a custom printer mapping file on Windows Server 2008, see deze link for the Windows Server 2008 R2 version.
Ask the Performance Team - Terminal Server and Printer Redirection
Remote Desktop Services (Terminal Services) Team Blog - Using Remote Desktop Easy Print in Windows 7 and Windows Server 2008 R2
Brian Madden - Managing Printer Drivers voor Windows Server 2003.

Miscellaneous

Remotely turn on RDP

Open regedit create a connection to the registry of the remote machine. Change the following key value to 0:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server]
"fDenyTSConnections"=dword:00000000

Now the system has RDP enabled. An RDP connection should now be possible if no further (network)restrictions like (Windows) firewall are in place.

No valid software license was available

A Windows Server 2003 Terminal Server is set to use the license server that grants per user licenses. After logging in to a Juniper SA and setting up an RDP session the following message appeared:

Windows Terminal Server Proxy
No valid software license was available.

Forgot to specify “Per User” with the license server settings on the Terminal Server.
The first error on TechNet - Troubleshooting Remote Desktop Licensing Error Messages gave the clue.

Update the shadow key timestamp

Sometimes you need to update or add registry keys to the shadow key on a Terminal Server.
To let the new keys apply to new user logins, you have to manually update the timestamp key after adding/modifying the registry keys.

Do this:

Modify/add the registry keys
Calculate the number of seconds since 1 januari 1970 (see UTC calculator link)
Modfiy the value of the LatestRegistryKey DWORD below HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\IniFile Times with this new value

Sources:
Ask the Performance Team - Terminal Services - Exploring the Shadows
UTC seconds calculator

Copying files from RDP results in corrupt files

Windows Server TechCenter > Windows Server Forums > General > Issue with copying files using RDPClip.exe rather than RDP Mapped Drives
Citrix Knowledge Center> Support Forums > XenApp (Presentation Server) > XenApp 5.0 for Windows Server 2003 / Presentation Server 4.5 > Presentation Server 4.5 - General > File Transfer issue with RDPClip.exe rather than RDP Mapped Drives

Query the Session Broker / Connection Broker via WMI

Clusters:

Get-WmiObject Win32_SessionDirectoryCluster | Select-Object ClusterName,NumberOfServers | Format-Table -AutoSize

Servers:

Get-WmiObject Win32_SessionDirectoryServer | Select-Object ServerName,ClusterName,NumberOfSessions,ServerWeight | Format-Table -AutoSize

Via: Microsoft - Windows Server Forum - How to read the RD Connect Broker DataBase!!!!

Server 2012 R2 RemoteApp connects to RDWeb/Gateway instead of session host

Problem: When starting a RemoteApp from the RDWeb page that connects via an RD Gateway to 1 of 2 session hosts the RemoteApp tries to connect to the host address of the RDWeb/Gateway server instead of one of the session hosts / the farm address.

If you download the rdp file that gets downloaded from the RDWeb page (don't use IE, use Firefox), open it in Notepad, and change the RDWeb/Gateway address in the line “full address:s:Name OF RDWeb/Gateway server” to the FQDN farm address the RemoteApp works.

Workaround (fix?): Add the full address of the RD Farm to the CustomRdpProperty on the Session Collection with powershell:

Set-RDSessionCollectionConfiguration -CollectionName "Name of RD Session Collection" -CustomRdpProperty "use
 redirection server name:i:1 `n full address:s:rdfarm.domain.com"

Replace “Name of RD Session Collection” with the name of your RD session collection.
Replace rdfarm.domain.com with the FQDN of your (internal) RD Farm.

Source for the PowerShell option: Server Fault - RDS, RDWeb, and RemoteApp: How to use public certificate for launching apps on session host?

Table of Contents

Microsoft - Terminal Server / Remote Desktop

Documentation

MS KB Articles

Server 2012

Firewall

RD Licensing

Articles/Blogposts

Windows Server 2012 / R2

Blogs

Clients