WebDAV: Increasing Maximum File Size Limit in Windows Server

Windows (IIS) server based WebDAV server has “laughable” file size limit for download or uploads to/from the server. It turn out to be the restriction is on the client side (Windows). Microsoft says the reason for this restriction is,

This issue occurs because a security change that was introduced in
Windows XP SP2 affects the Web Distributed Authoring and Versioning
(WebDAV) redirector. This security change makes sure that an
unauthorized server cannot force a client computer into a denial of
service attack. If you try to download a file that is larger than
50000000 bytes, the client computer interprets this download as a denial
of service attack. Therefore, the download process stops.

Also it’s fixable. Too bad we have to fix this for every client machine that needs to use WebDAV with huge files. It is documented at http://support.microsoft.com/kb/900900.

The fix is also described in above KB article. You can also see fix below as per in the KB article.  

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
3. In the right pane, right-click the FileSizeLimitInBytes value, and then click Modify.
   If you cannot see the FileSizeLimitInBytes value, right-click the blank space in the right pane, click New, click DWORD Value, type FileSizeLimitInBytes, and then click OK.
4. In the Edit DWORD Value box, click to select the Decimal option. In the box under Value data, type a value that is larger than the size of the file that you want to download. Click OK.
   Note The default value for the file size limit is 50000000 bytes.
5. Quit Registry Editor. Restart the computer.

Unfortunately I didn’t find any server side solution, since Windows clients are set to restriction.