I had exactly the same problem - My DELL Vostro 3550 has no Pause/Break key ... but I need one in order to operate the software that we wrtie correctly.
Eventually I managed to get this working by adding a new KEY to the Registry. (I am running Win7 Professional)
1) clcik the START, then type REGEDIT into the search box. This will start the registry editor.
2) Explore the Registry, expanding each element
HKEY_LOCAL_MACHINE
-SYSTEM
-Current Control Set
- Control
- Keyboard Layout
Click on the Scancode Map, and EDIT the key values to match that shown below.
i.e. to have values of : 00,00,00,00,00,00,00,00,
02,00,00,00,
46,e0,44,00,00,00,00,00
Once Done you will need to re-boot your laptop, but after that you can use <Ctrl><F10> as the pause/Break Key.
(Option)
If you want you can copy/Paste the text below into a *.txt file.
Save the file onto your desktop and rename as New_Reg_Key.reg because of the *.reg extension you can then double_click the file to add the new registry key.
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout]
"Scancode Map"=hex:00,00,00,00,00,00,00,00,02,00,00,00,46,e0,44,00,00,00,00,00
I hope this is some use to others.