Csc.exe is broken? Help!

I downloaded the .NET 3.5 SDK last night, did a search on csc.exe, found it in:

C:\WINDOWS\ServicePackFiles\i386

... and added it to my PATH environment variable. Now, when I try to execute the compiler from the command line, it tells me:

fatal error CS2018: Unable to find messages file 'csccompuni.dll'

... thoughts?

Don't panic.

This is a traditional rite of passage that all new C# developers go through in first attempting to use the free SDK. Welcome to the community.

Here's the deal: a version of csc.exe has been installed with every service-pack and dot-revision of .NET, back to the dawn of time or whever you bought your box. My box was purchased last year and I have five of them. You probably do, too, if you just let the Search run on. What most folks do is see one csc.exe pop up (the wrong one - in fact the earliest one installed, now with its directories snarled up and its paths-to-critical-dlls tangled), then stop the search and copy that executable's path into PATH. Result is ... well, bad.

The one you want is the 3.5 one, usually the last to pop up in Search. On my system that's in:

C:\WINDOWS\Microsoft.NET\Framework\v3.5

When you copy THAT csc.exe's path into PATH, life will probably be beautiful for you.

I assure you, moreover, that this will be the last frustrating experience you ever have as a C# developer. All that awaits you now are blue skies and infinite horizons.

It totally worked. Thanks!