[Legacy] Stopping Net Send / WinPopup Messages on Windows XP
Watch out, legacy content ahead! PaperCut historically has been able to leverage Microsoft’s WinPopup feature to send messages to Windows clients over the network, which has worked for many customers as an alternative to running the PaperCut User Client, however you should know that WinPopup has been officially deprecated for some time so we do not recommend considering this option for any new installations.
Q How can I stop users from using (abusing!) “net send” or WinPopup on Windows XP?
PaperCut can use “net send” to issue messages to users. Enabling this feature however allows end-users to send popup messages to other users. Windows XP SP2 introduced a new registry key that can be used to make it so that only administrators can send messages using “net.exe” or any program that uses the NetMessageBufferSend API function. Using this method to disable messages is very useful in schools or universities as it not only stop abuse of “net.exe” but any application that uses the API directly.
If you are using PaperCut NG or ChargeBack, then the user client can also be used to deliver messages. This is more reliable than Net Send and can also be used on non-Windows systems (e.g. Mac and Linux).
Note: This is only available on XP systems with SP-2 installed.
- 1. Click Start, click Run, type regedit, and then click OK.2. Locate and then click the following key in the registry:
System\CurrentControlSet\Services\LanmanWorkstation\Parameters3. On the Edit menu, point to New, and then click DWORD Value.4. Type
LimitMessageSend, and then press ENTER.5. On the Edit menu, click Modify.6. Type 2, and then click OK.A value of 2 will restrict the use of messages to “Administrators Only”.More information on this change is available at:
For ideas on controlling messages on other Windows versions, please see the article [Legacy] Working with popup messages.
Keywords: net send, popup messages, pop-up messages, user notification, abuse of net.exe