We are running Exchange 2010 SP3. Latest update rollup. A user reported today that they get a sending error trying to email a picture to another user using ActiveSync and their mobile device.
I verified this is the case. Seems like smaller pics go through like 5MB but larger ones do not. You can successfully send to a gmail account but not another user on Exchange.
I found this article below but it is for Exchange 2013, not Exchange 2010. The folders they reference don't exist nor do the virtual directories in IIS.
Based on some other information I found, it looks like you just need to modify the web.config file on the CAS role server, at least for 2010 anyway. I was going to change the values for MaxDocumentDataSize andMaxRequestLength in the web.config on each CAS server to 29696 (29 x 1024) to get as close to our Exchange Global limit of 30MB. Is there anything else I need to change?
https://technet.microsoft.com/en-gb/library/hh529949(v=exchg.150).aspx