WCF - How to Increase Message Size Quota

If you're still getting this error message while using the WCF Test Client, it's because the client has a separate MaxBufferSize setting.

To correct the issue:

1. Right-Click on the Config File node at the bottom of the tree
2. Select Edit with SvcConfigEditor

A list of editable settings will appear, including MaxBufferSize.

Note: Auto-generated proxy clients also set MaxBufferSize to 65536 by default.

You'll want something like this to increase the message size quotas, in the App.config or Web.config file:

<bindings>
    <basicHttpBinding>
        <binding name="basicHttp" allowCookies="true"
                 maxReceivedMessageSize="20000000" 
                 maxBufferSize="20000000"
                 maxBufferPoolSize="20000000">
            <readerQuotas maxDepth="32" 
                 maxArrayLength="200000000"
                 maxStringContentLength="200000000"/>
        </binding>
    </basicHttpBinding>
</bindings>

And use the binding name in your endpoint configuration e.g.

...
bindingConfiguration="basicHttp"
...

The justification for the values is simple, they are sufficiently large to accommodate most messages. You can tune that number to fit your needs. The low default value is basically there to prevent DOS type attacks. Making it 20000000 would allow for a distributed DOS attack to be effective, the default size of 64k would require a very large number of clients to overpower most servers these days.

If you are creating your WCF bindings dynamically here's the code to use:

BasicHttpBinding httpBinding = new BasicHttpBinding();
httpBinding.MaxReceivedMessageSize = Int32.MaxValue;
httpBinding.MaxBufferSize = Int32.MaxValue;
// Commented next statement since it is not required
// httpBinding.MaxBufferPoolSize = Int32.MaxValue;