I discovered that my E-Mail server started having issues with DNS lookups. This does not sound as though it is a bad thing. However, it turned out to be a big issue. A reboot fixed all problems, but I now am faced with hundreds of E-Mail messages because of the DNS lookup failures (since I configure my E-Mail server to use a DNS Black Hole list). Unfortunately, the only solution is to sift through the junk. This, of course, will take time.