error while importing or exporting mp3 files

I am getting a “Cannot Open Library” error while importing and exporting. I have the lame incoder installed. I am using Audacity 2.0.3. And I installed from Audacity from the Audacity.exe file.

LAME is not used for importing files, only for exporting MP3.
Which version of Windows are you using?
Which (exact) version of Audacity are you using (look in “Help menu > About Audacity”)
What is the full error message?