When you upload a large file (over 50Mb usually) to SharePoint 2010, you might get an "Error 0x800700DF: The file size exceeds the limit allowed and cannot be saved" message. Obviously, the first thing you need to check is to ask your SharePoint administrator what is your current file size upload quota. If the quota is not a problem, then the error is most likely caused by a local restriction set on Web Client service. By default, Web Client file size limit is set to 47Mb or so. To increase this limit:
- Open Windows Registry using regedit command
- Browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
- Right click on the FileSizeLimitInBytes and click Modify
- Click on Decimal, and type 4294967295 and click OK
- Restart Web Client service using Services snapin.
This will increase the Web Client file size limit to 4Gb, which is a maximum file size you can upload using WebDAV. Please note, that this will only address Web Client service restrictions, and will not increase your SharePoint quota. Only your SharePoint Administrators can do that, so be nice to them J