It does not matter whether you send the letter via email or snail mail—as long as ... (The first paragraph is a simple thank you, and reminds the recruiter about the position for which you interviewed ...

Following an interview, write your interviewer a brief thank-you letter. This common courtesy ... job for which you interviewed because some recruiters might be conducting multiple job searches.

Recruiters should strive to treat every candidate as a top priority, but sometimes, internal priorities do take precedence. If you feel ghosted after sending your thank you note, you could try ...