Visual C++ Remote Debugging - Breakpoints Become Disabled

Question

Here's the setup I have:

• On my local PC I build an un-managed C++ app in release mode, with debug information
• On my local PC the .exe and .pdb file are in the same dir
• On my local PC this works, I can debug as expected
• On the remote PC I copy both of these files into a \bin folder
• In my remote debugging settings I tell it to run in the \bin folder
• When I run up the .exe through the remote debugger, it is launched on the remote PC but all my breakpoints become disabled
• I don't get popups warning me about missing debug information, which suggests it can find the PDB file but is not able to use it right

Any ideas why? I take it the remote PDB file is the one used? Or is my local PDB file used by my local debugger as it talks to the remote .exe?