Configure Outlook Web Access (OWA) 2003 Attachment Blocking

There are 2 levels of file attachments for Outlook Web Access. Level1 attachments have file extensions that are prohibited from accessing by OWA. Level2 attachments have file extensions that can be accessed, but only if saved to the client's file system first.



OWA is installed with a default set of file extensions for the two levels as shown in the following registry keys:

Level 1 attachments

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeWeb\OWA

Value: Level1FileTypes

Type: REG_SZ
Value Data:

ade,adp,app,asx,bas,bat,chm,cmd,com,
cpl,crt,csh,exe,fxp,hlp,hta,inf,ins,isp,js,jse
,ksh,lnk,mda,mdb,mde,mdt,mdw,mdz,msc
,msi,msp,mst,ops,pcd,pif,prf,prg,reg,scf,scr,
sct,shb,shs,url,vb,vbe,vbs,wsc,wsf,wsh

Level 2 attachments

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeWeb\OWA

Value: Level2FileTypes

Type: REG_SZ

Value Data:

ade,adp,asx,bas,bat,chm,cmd,com,cpl,crt,exe,hlp
,hta,htm,html,htc,inf,ins,isp,js,jse,lnk,mda,mdb,mde,
mdz,mht,mhtml,msc,msi,msp,mst,pcd,pif,prf,reg,scf,scr,sct
,shb,shs,shtm,shtml,stm,url,vb,vbe,vbs,wsc,wsf,wsh,xml,dir,dcr,plg,spl,swf

Attachments listed should be separated by a comma with no space.