SecureBlackbox 16: Explorer fails to download huge files with " Error 0x800700DF ". What should I do?

Note: This article applies only to SecureBlackbox Legacy. For future development please consider using the latest version.

Windows clients have a hard-coded limit of the file to be downloaded via WebDAV. This limit is set to 50,000,000 bytes (less than 50 MB). The limit per set can't be removed, but it can be set to 4 GB on the client. To fix the issue, you need to open the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters key in the registry (on the client computer!) and set the FileSizeLimitInBytes parameter to 0xFFFFFFFF .

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