Intellisense stops working in VWD 2010

I'm working with VWD2010 and as stated in the topic title I have zero intellisense usability for my project.

I installed VWD2010 fresh a few months ago to start and noticed that intellisense wasn't working. For the last three months I was working with VS2010 trial and intellisense was working fine. The trial version expired, so now I am back to VWD2010.

Intellisense seems to work for NEW projects, so I created a new project and transferred all my files from the VS2010 project. Intellisense was working fine for a couple of days, but this morning I am back with it not working...

I have checked the following:

Intellisense works for new projects;
Intellisense is switched on in the editor settings;
I have reinstalled VWD2010 several times before without it making the blindest bit of difference;
I have reset settings both via the Options menu and via the command line, again without it making the slightest bit of difference.

Intellisense was definitely working for this project last Thursday evening when I last switched off my computer.

I have googled this issue several times and can't find the slightest bit of info on how intellisense is actually supposed to work. Advice generally resumes to "reinstall VWD" or "reset your settings"... Any help would be greatly appreciated.

Here is a distillation of some solutions that have worked for other users from the MSDN forum thread IntelliSense stopped working:

In Visual Studio, Go to Tools > Import and Export Settings, and then select Reset all settings.
After closing Visual Studio, move the .suo file to a temporary folder, and then reopen Visual Studio.
Check that Build Action property of your source files are set to Compile rather than Content. Setting a file to Content detaches the source file from the rest of the project, disabling IntelliSense.
If you have a web project, exclude the WebConfig from the project and rebuild the project. Then include the WebConfig.file again.
If you’re using C++, close Visual Studio, and then delete the .ncb file. The ncb file contains IntelliSense information for C++. Deleting it resets IntelliSense, but it may take a while to rebuild in the background.