DLL-Files.com Support says:
Are you getting an error with title "Wireless configuration"
Error text: "Notification dll has not been registered, program will not work properly"?
This error is not regarding a file named "notification.dll", but for a dll-file used for notifications. The program trying to load this file seems to be the Broadcom Wireless Network Tray Applet (bcmwltry.exe), and the dll-file in question would be "wltrynt.dll". The solution for this error, is to register the notification dll-file (wltrynt.dll).
How to register the "wltrynt.dll" on a 32bit (x86) Windows system;
Open an elevated command prompt.
To do this, click Start, click All Programs, click Accessories, right-click "Command Prompt", and then click Run as administrator.
In Windows 8, go to the Start screen. Start typing cmd and Windows will find "Command Prompt". Right click "Command Prompt" and choose Run as administrator.
If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.
Type regsvr32 wltrynt.dll and press Enter.
on a 64bit windows:
Open an elevated command prompt, as instructed above.
In the command prompt, start by typing :
and press enter.
then type the following and press enter: