Attachment filter: Provide the "Discard zip archive containing files with dangerous extensions" option by extension and not globally.
Generally we want to filter zipped and not zippend attachements. But for some extensions we need a method to let them through to not break our business processes (e.g. we need to allow zipped .xlsm and .docm files) and block everything else.
David Hepper commented
This can be implemented simply by making the test for 'dangerous extensions' use the Filter Rules defined below. Currently the test used by the 'Discard zip archive...' feature seems to be built into Kerio and invisible to users.
We have the opposite problem to Peter! We want to *filter* attachments such as .xlsm, so we have created a rule to block them. However, currently (KC9.2.2) if I receive a zipped file named test.xlsm it is allowed through even when the 'Discard zip archive...' checkbox is set.
Oh, and a .zip containing a .zip should always be filtered.