Antivirus  solutions  using  Extensible  Storage  Engine  API  or  any 

other undocumented API may corrupt the Information Store and its 

databases 

  The Microsoft Exchange product group does not provide any code 

updates, documentation, or technical assistance to address issues 

related to the use of a non VS API based solution 

  For  Exchange  customers  using  a  non VS  API based  solution, 

Microsoft  Product  Support  Services  may  ask  the  customer  to 

uninstall/disable the anti virus solution to help identify issues, this 

may delay in final resolution 

  VS API enhances the current core feature set by providing abilities 

to optimize and configure the scanning process at multiple levels, 

as  well  as  providing  Exchange  administrators  with  built in 

functionality to monitor the performance of the new API  

For more information about VS API 

You can find more information about VS API on this link: 

http://support.microsoft.com/default.aspx?scid=kb;EN US;q285667 

Limitations of using the VS API Exchange 2000/2003 mode 

Although VS API is a recommended way to do content checking and 

virus  scanning  on  Exchange  2000,  there  are  a  number  of  limitations 

which you need to be aware of as a system administrator: 

1. The Virus API only scans information stores. That means that if you 

have installed GFI MailSecurity for Exchange 2000 on for example a 

front end  server,  no  mail  will  be  scanned,  because  mail  is  not  being 

stored  on  the  front end  server.  In  this  case,  you  need  to  use  GFI 

MailSecurity in SMTP gateway mode. 

2. You need to be more careful with applying attachment rules. Some 

MAPI  applications  running  on  Exchange  might  be  using  vbs  or  exe 

files. You need to ensure that if this is the case, you don't apply rules 

to quarantine exe or vbs files to mailboxes used by those applications. 

3. Outgoing mails that have been approved need to be resent by the 

user. For example, if an executable is quarantined and approved, the 

user  will  get  a  message  saying  that  he  has  24  hours  to  send  that 

executable.  The  reason  for  this  is  because  the  recipient  of  the 

message is not always known with 100% certainty in VS API mode. 

GFI MailSecurity SMTP gateway mode 

If  you  do  not  need  to  scan  internal  mail  or  do  not  have  Microsoft 

Exchange  2000/2003,  you  must  install  GFI  MailSecurity  in  SMTP 

gateway  mode.  You  can  install  GFI  MailSecurity  in  SMTP  Gateway 

mode on a separate machine on the perimeter of your network (acting 

as a mail relay) or on the Exchange server 2000/2003 machine it self. 

The SMTP gateway mode allows you to set up more powerful content 

security rules. If you do not need to scan internal mail we recommend 

the SMTP gateway mode. 

4 

 Explaining GFI MailSecurity