We have a setup of Exchange 2010 organization in which we only have OWA users. our requirement is that the users can only send four type of attachements and those are: word, excel, pdf and jpeg/jpg files.
I also have forefront for exchange 2010 on hub servers. i created a filter rule and checked all file types by inspection and only unchecked / allowed the four files. After that every attachement was blocking so i drill down the filters and came to know that i have to allow txt and Microsoft transport neutral encapsulation format to allow any other file attachment if users are using OWA.
After allowing in section of Micorosoft office filter, i have only blocked MDB files and all others are allowed.
while applying this filter i tested and found that the required file attachments are allowed but many other attachements are also allowed. i tested the attachment .evt and aspx which pass thru the filter and not blocked by Forefront.
In Simple our requirement is to allow only four extensions (Word, Excel, PDF, JPEG) and block rest of all extensions.
What is the way to do this Please ?