Installation manual

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3.2.1.1 Virus-Scanning Application Programming Interface (VSAPI)
Microsoft Exchange Server provides a mechanism to make sure that every message component is scanned against
the current virus signature database. If a message was not previously scanned, its corresponding components are
submitted to the scanner before the message is released to the client. Every supported version of Microsoft
Exchange Server (5.5/2000/2003/2007/2010) offers a different version of VSAPI.
3.2.1.1.1 Microsoft Exchange Server 5.5 (VSAPI 1.0)
This version of Microsoft Exchange Server includes VSAPI version 1.0.
If the Background scanning option is enabled, it allows for scanning of all messages in the system background.
Microsoft Exchange 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.
3.2.1.1.1.1 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 field allows you to set Attachment deletion method to either of these options:
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 informationESET 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.
3.2.1.1.1.2 Performance
During a scan, Microsoft Exchange Server allows you to limit a time for opening message attachments. This time is
set in the Response time limit (ms) field and represents the period after which the client will retry accessing the
file that had previously been inaccessible due to scanning.
3.2.1.1.2 Microsoft Exchange Server 2000 (VSAPI 2.0)
This version of Microsoft Exchange Server includes VSAPI version 2.0.
If you uncheck the Enable antivirus and antispyware VSAPI 2.0 protection option, the ESET Mail Security plug-in
for Exchange server will not get unloaded from the Microsoft Exchange server process. It will only pass through the
messages without scanning for viruses. The messages however, will still be scanned for spam and the rules
will be applied.
If the Proactive scanning option is enabled, new inbound messages will be scanned in the same order in which
they were received. If this option is enabled and a user opens a message that has not been scanned yet, this
message will be scanned before the other messages in the queue.
The Background scanning option allows scanning of all messages in the system background. Microsoft Exchange
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