IS it possible to deploy my WP7 app on a WP 7.8 device

As part of a course module I have to develop a mobile application. I chose to develop a Windows Phone app only to learn that WP SDK 8 cannot run on my 32 bit Windows 7 laptop. But I downloaded the WP 7 SDK and developed my app. I can register for a student account and unlock a device to demo my app at my project presentations, but sadly I learn now that apps built on the WP7 SDK cannot be deployed on WP8 devices, so I will not be able to use the Lumia 520 I had intended to use for my demo. I am in quite a fix now.

IS it possible to deploy my WP7 app on a WP 7.8 device? That seems like the last resort since a friend of mine has a WP 7.8 phone.

Any other suggestions are mostly welcome!

Yes, of course. I have a Lumia 800 which runs WP 7.8 and I deployed my apps there when working with Visual Studio 2010 and the old SDK.

Btw: When developing for WP you should really install a x64 OS. You could use a spare partition on your laptop. I think you can get Windows 8 for free via Dreamspark.

So if nothing works and you're running out of time for your demo you could set up the whole thing on a fresh system within 3 hours. Even less if you have the ISO installation files.

That isn't true. WP7 apps can be deployed to WP8 devices. However, you do have a problem because deploying an app to a WP8 device requires WP8 SDK, which in turn requires Windows 8.

It shouldn't be a problem to deploy to your friend's WP7.8 after you unlock it.

    WP7 apps can be deployed to WP8 devices. However, you do have a problem because deploying an app to a WP8 device requires WP8 SDK, which in turn requires Windows 8.
With the WP7 SDK, you can write applications that work on all Windows Phone 7.x and 8.x devices.  As you have a Microsoft Account since you are able to unlock a phone for side loading an application, you also have the possibility of creating a "Beta" release on the Windows Phone Store.  With the beta release, you can install the application on Windows Phone 7.x and 8.x devices without having to unlock the phone for testing or for your demo.