You need to file a police report in town where you live ( for theft of check and forgery). Also probably file with the US postal inspector since check was stolen from the mail. Ask your employer to get you a copy of front and back of check. You need to sign a Forgery Affidavit so that your employer can give that to his bank and get the money back into his account. Then he should issue a replacement check to you. Act quickly since 6 months have passed. A form of Forgery Affidavit can be found on Internet by google or on FTC website.
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