Large Attachments Not Downloading

Hello,

In my line of work (Printing), it is very common for me to receive large email attachments. I try to set clients up with online dropboxes and FTP so we can share large files outside of email, but this step, unfortunately, is often times a reactive measure.

From time to time, I'll get a real clogger of an email that forces me to go into my webmail to download the file(s) and then remove the clogging email, which can be a real pain in the butt.

I was using Mac Mail (v6.6), but as a test to see if it would clear up the issue I switched to Thunderbird (17.0.8). The issue has not been resolved.

I am unsure what the max file size is, but the lowest I've seen clog my email is around 8 MB. I suspect there is a setting on my Mac somewhere preventing "large" attachments from coming through since switching email programs had no effect. I should point out that I do receive these large attachments on my iPhone, and the same "large" emails can be received from other Windows users here.

I checked with my email provider, but they were unable to figure it out.

I found this KB that I thought might be a step in the right direction, but it's for OS X Server. Is there a similar setting that can be adjusted on a non-server version of OS X? http://support.apple.com/kb/HT5627

My email account is an IMAP.

Here are the specs for my iMac:

OS X 10.8.5

2.7 HGz Intel Core i5

8 GB 1600 MHz DDR3

Not sure if it matters, but I'm using avast! for my AV.

Thanks,

RL