It's convoluted but here is the method I used, and this got it installed in Win7, even shows in WMP encoder list.

Right click on Command prompt and 'Run as Administrator' (that may scare some already).

I downloaded and unzipped the ACM file from Rarewares (which is linked to from the Lame site).
http://www.rarewares.org/mp3-lame-dshow-acm.php#lame-current-acm

There is a 'how to install' txt file in the package, follow it exactly including moving files to C:\Lame.

Copy all the extracted files to a new empty folder called C:\Lame in order for the following command lines to work. THIS IS IMPORTANT.

Now, in your Command prompt (running with admin rights) insert the following and copy/paste it to be exact. You have to right-click to paste into a Command prompt.

cd %windir%\SysWOW64

Hit Enter
Command prompt should change directories

Then copy/paste
rundll32 setupapi.dll,InstallHinfSection DefaultInstall 0 C:\lame\LameACM.inf


This was found at http://windows7themes.net/installing-lame-on-windows-7-x64.html (so you know the source).

Following directions closely worked for me on this new W7 professional machine.

See below for how it lists in RB compressed export options (all bitrates available)

As always download safely; scan before installing, not after! I'm not vouching for links, just that it worked as of today.

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