Comment A tool claims to be able to but the claim is bogus (Score 1) 467
In Q2 2009, a company called Forensic Innovations, Inc. claimed to be able to distinguish random data from TrueCrypt containers. See http://www.forensicinnovations.com/blog/?p=7
However, I downloaded their tool (Version 2.23 of File Investigator TOOLS) and it identified truly random data as a truecrypt container... In fact it identified any container of truly random data bigger than a certain size as encrypted data.
Therefore, their $249 tool (or this particular version at least), which claims to "Detects Encrypted Files, including TrueCrypt" is not performing as advertized. Try it for yourself.