The NumLock status may become out of sync during a Remote Desktop session.

Source: Microsoft Support

RAPID PUBLISHING ARTICLES PROVIDE INFORMATION DIRECTLY FROM WITHIN THE MICROSOFT SUPPORT ORGANIZATION. THE INFORMATION CONTAINED HEREIN IS CREATED IN RESPONSE TO EMERGING OR UNIQUE TOPICS, OR IS INTENDED SUPPLEMENT OTHER KNOWLEDGE BASE INFORMATION.

In certain rare scenarios, when connected to a system using Remote Desktop, the status�of the NumLock key may go out of sync between the host and client systems.� This typically can be seen on slower dial-up connections or if system resources are low on either system.� Repeatedly pressing or holding down�the NumLock key can cause this behavior.

The number pad may not function as expected on the client system.

A few things can be done to prevent any problems with the function of the number pad and NumLock status during a Remote Desktop session.

1. Upon first connecting to the remote system, verify the current status of the NumLock key by testing its functionality anywhere text input can be performed; for example, in Notepad.
2. When cycling the NumLock status, press the key once, then wait and verify the status of the number pad before pressing the NumLock key again.
3. Avoid holding down the NumLock key, or pressing the key multiple times.
4. On slower connections, change the connection type under the Experience tab of the Remote Desktop Connection client to match the physical connection speed to the host.� Or, set the connection speed to be lower than the physical connection speed to the host.

This problem�occurs very rarely,�though it may be seen more frequently if a user is connected to a virtual machine through Remote Desktop.

MICROSOFT AND/OR ITS SUPPLIERS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY, RELIABILITY OR ACCURACY OF THE INFORMATION CONTAINED IN THE DOCUMENTS AND RELATED GRAPHICS PUBLISHED ON THIS WEBSITE (THE �MATERIALS�) FOR ANY PURPOSE. THE MATERIALS MAY INCLUDE TECHNICAL INACCURACIES OR TYPOGRAPHICAL ERRORS AND MAY BE REVISED AT ANY TIME WITHOUT NOTICE.

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, MICROSOFT AND/OR ITS SUPPLIERS DISCLAIM AND EXCLUDE ALL REPRESENTATIONS, WARRANTIES, AND CONDITIONS WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING BUT NOT LIMITED TO REPRESENTATIONS, WARRANTIES, OR CONDITIONS OF TITLE, NON INFRINGEMENT, SATISFACTORY CONDITION OR QUALITY, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THE MATERIALS.