Exchange comes with some default limits on attachment size and file types. this is for security as well as stability- without limits a user could send a 1 Gb movie to a distribution list, which would seriously hamper your server. I am typically good with defaults, but I am having an issue with Sharepoint. I can not seem to upload a 500Mb PowerPoint presentation. I tried upload from the site, I tried file copy in windows explorer. I then broke the file in half, and still can’t get it over. So I thought I would email it to my list- I do have several libraries mail enabled.

Exceed File Size

Exceed File Size

The file is 117 Mb. That is not too big for Outlook or Exchange, though it is for my Sharepoint. And yes, I changed the connection timeout and the file size limit in CentralAdmin- still got nothing.

To change the max attachment size in Exchange 2007, open up Exchange Management console. Expand Organization configuration and click on Hub Transport. Click on the Global Settings tab, and double-click Transport Settings. Change the first two values to what fits your needs. I changed mine to 1 Gb each- I will be changing them back after I send this file.

Transport Settings

Transport Settings

this can also be done in the Active directory.

Click Start>Run and type mmc.exe

Click file, add or remove snap-in.

Click ADSI Edit, and Add. Click Ok.

In the console that opens, right-click ADSI Edit, and click Connect to.

Select the radial button that says A Well Known Naming Context, and select Configuration.

Connect Configuration

Connect Configuration

Click Ok.

Expand Configuration>CN…>Services>Microsoft Exchange>first Organization>Global Settings>

Right click Message Delivery and select properties.

Change these attributes to manipulate the size values:

delivContLength – incoming message size limit (default is 10240)

submissionContLength – receiving message limit (default is 10240)

Message Delivery Properties

Message Delivery Properties

Close out everything you did, and go back to Outlook… Oh no! You STILL cant attach the file. Well if Exchange is not stopping you anymore, what is? Outlook itself?

Outlook 2010 restricts message size to 20 Mb. Lets change this as well.


Type regedit and click open.

Navigate to HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences

Right click the folder and select new DWord Value. Name the new key MaximumAttachmentSize.

Right click the new key, select decimal, and enter the size you want to increase it to. I used the same value I used in Exchange 2007, or 1024000.

Restart Outlook, attach away.

Remember, messing with the registry can brick your system. Backup first, and write down what you did so that if errors occur, you can reverse them easily.

There is one more setting that supposedly changes the way your site handles attachment size, which is done wy adding some code to the web.config file for one of your site’s pages. I will not get into it, as I did not do it. Google search for it and you will come up with a few sites.