Beginner: SDK manager fails, Eclipse fails to load ADT

I can run the emulator from the command prompt and start it from the desktop (Win7 32-bit) using a batch file, but it doesn't run from the SDK Manager.

Also, I have installed Eclipse, but when I try to load the ADT Plugin, it seems to run then I get

"Cannot complete install because one or more required items cannot be found"

I've tried changing https to http. No difference. If开发者_运维百科 I cancel any of the ticks beside the list of 4 installation components, the "Next" box is no longer greyed out.

Any clues as to what I'm doing wrong?

Do you have two different parttions such as a C drive and a D drive? or have you migrated your user profile to another drive? If so that's your issue