Installation manual

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Server decides whether a background scan will run or not, based on various factors, such as the current system
load, the number of active users, etc. Microsoft Exchange Server keeps a record of scanned messages and the virus
signature database version used. If you are opening a message that has not been scanned by the most current virus
signature database, Microsoft Exchange Server sends the message to ESET Mail Security to be scanned before
opening the message in your email client.
Since background scanning can affect system load (scanning is performed after each virus signature database
update), we recommend using scheduled scanning outside working hours. Scheduled background scanning can be
configured via a special task in the Scheduler/Planner. When you schedule a Background scanning task you can set
the launch time, the number of repetitions and other parameters available in the Scheduler/Planner. After the task
has been scheduled, it will appear in the list of scheduled tasks and as with the other tasks, you can modify its
parameters, delete it or temporarily deactivate the task.
If you want to scan plain text messages, select the Scan plain text message bodies option.
Enabling the Scan RTF message bodies option activates scanning of RTF message bodies. The RTF message bodies
may contain macro viruses.
3.2.1.1.2.1 Actions
In this section you can specify the actions to be performed when a message and/or attachment is evaluated as
infected.
The Action to take if cleaning not possible field allows you to Block infected content, Delete the message or take
No action on the infected content of the message. This action will be applied only if the automatic cleaning
(defined in ThreatSense engine parameter setup > Cleaning ) did not clean the message.
The Deletion option allows you set Message deletion method and Attachment deletion method.
You can set Message deletion method to:
Delete message body – delete the body of the infected message; the recipient will receive an empty message
and any non-infected attachments
Rewrite message body with action information – rewrite the body of the infected message with information
about performed actions
You can set Attachment deletion method to:
Truncate file to zero length – ESET Mail Security truncates the attachment to zero size and lets the recipient see
the attachment file name and type
Replace attachment with action information – ESET Mail Security replaces the infected file with a virus
protocol or rule description
By clicking the Rescan button you will run another scan on messages and files that have already been scanned
before.
3.2.1.1.2.2 Performance
In this section you can set the number of independent scan threads used at a single time. More threads on
multiprocessor machines can increase the scan rate. For the best program performance we advise using an equal
number of ThreatSense scan engines and scan threads.
The Response time limit (sec.) allows you to set the maximum amount of time a thread waits for a message scan
to complete. If the scan is not finished within this time limit, Microsoft Exchange Server will deny the client access
to the email. Scanning will not be interrupted and, after it is finished, every other attempt to access the file will be
successful.
TIP: To determine the Number of scan threads the Microsoft Exchange Server provider recommends, use the
following formula: [number of physical processors] x 2 + 1.
NOTE: Performance is not improved significantly if there are more ThreatSense scanning engines than scanning
threads.
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