Disabling AMP is a workaround, but I wouldn't call that a solution. The issue is due to a bug and Meraki has a fix in a beta firmware (15.12). ... View more

The fix is in MX firmware beta 15.12 or greater.  We have been testing for weeks and no issues now with AMP enabled.  Whitelist exclusions appear to be working also.  No other issues reported with this firmware in our environment so far. Contact Meraki to request testing 15.12 -- only they can provide it.   ... View more

Cisco Meraki acknowledged this is a bug around Sept 2018 for us.  The fix has been in development for months and it is a problem with the AMP engine.  We check in weekly with our technical contact and they told us last week that 14.39 does not have any code included to address this, but upgrading can't hurt as some situations may differ.  Cheers! ... View more

We're experiencing similar issues with .Net downloads from and IIS server and PDF files for a paperless solution even with servers whitelisted.  As soon as we turn off AMP, everything sails through no problem.  And, as others have stated here, nothing in the logs so it's very difficult to troubleshoot.  We've spent several hours troubleshooting with Meraki support.  Issue happening on sable release firmware for MX (13.33) and BETA (14.31).  We're hopeful engineering can address quickly, but the issues have been time consuming. ... View more