There are no bug-free programs - Hellcore Mailer isn't exception here and may have more or less severe bugs. If you'll notice erroneous behavior or program won't work at all, feel free to post a bug report - either privately, by sending it to author at branch.prediction@gmail.com or using a program's discussion list at hcm-int@yahoogroups.com (subscribe by sending e-mail to hcm-int-subscribe@yahoogroups.com). Include everything that may be relevant to reproduce your bug, like what you were doing, what results were expected and what you actually got, any screenshots if possible, steps to reproduce your bug, any non-mainstream hardware you use, and so on. Note that no bug can be fixed if it cannot be confirmed. Author may not confirm it due to misunderstanding and/or lack of details. Also note that because program is in constant development, it may be a good idea to check for possible upgrades - maybe this bug is well-known and already fixed? In severe cases, you may even try a current snapshot. All are available from program's website.