Exchange Server 2007 has a default maximum accepted request length of 13MB. You may increase the maximum accepted request length by performing the following:

1. Open Windows Explorer.
2. Navigate to C:\Program Files\Microsoft\Exchange Server\ClientAccess\exchweb\ews
3. Open the file Web.Config in a text editor such as Notepad.
4. Find the XML tag starting with maxRequestLength=
5. Change the existing value to maxRequestLength="102400"
6. Save the file.
   
   Note: a value of 102400 represents 100 MBs in kilobytes.

Sample Web.Config before changes:

<configuration>
<system.web>
...
...
<httpRuntime maxRequestLength="13280" />
</system.web>
</configuration>

Sample Web.Config after changes:

<configuration>
<system.web>
...
...
<httpRuntime maxRequestLength="102400" />
</system.web>
</configuration>

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