Comment 22 for bug 1015405

The return value noted here is a scanning error code. This behavior has been seen on files that do not decompress correctly. If using clamav-milter, messages with attachments flagged as CL_EFORMAT trigger the OnFail Action specified in the clamav-milter.conf configuration file. The default Action for OnFail is Defer, so these messages will be rescanned at intervals and never delivered.

There is a workaround to break the loop of re-scanning these broken files. To reject messages with these attachments, change the OnFail Action to Reject. If you prefer the old behavior of the previous release, change the OnFail Action to Accept.

These solutions should be used as a temporary workaround only and in an environment where the connection to clamd is stable. Changing this configuration line will also affect any messages that fail scanning because of transient issues such as dropped connections or out of memory errors. If OnFail is set to Accept, malicious mail may be passed by the scanner. If OnFail is set to Reject, non-malicious mail may be rejected by the scanner. This workaround should be used with caution.