VS2010 SP1 Installation. "The feature you are trying to use is on a network resource that is unavailable"

Ultimately, I'm trying to install the windows phone app SDK so that I can put an app I've made on my phone.

To do this, I am told I need to install SP1.

When I attempt this I get the following:

"The feature you are trying to use is on a network resource that is unavailable visual studio riaservices.msi"

I download the riaservices.msi and point the dialog to it, and I get the message:

"The file is not a valid installation package for the product WCF RIA Services V1.0 for VS 2010."

I've downloaded the ISO as mentioned in a related post on this website, but I've no idea what I'm doing with that now it's mounted.

Some of the features I've tried to install have asked me to insert the CD which I don't have, I downloaded it for free from a university scheme.

An old problem, but for future readers...

Try using the MS FixIt found at the URL below to uninstall the offending program, "RIA Services" in this case. That will clean up the installation which appears to be the problem.

http://support.microsoft.com/mats/Program_Install_and_Uninstall