pbarnettms

Uploading files via browsers was a known issue. Please follow the workaround documented at https://docs.microsoft.com/en-us/hololens/hololens-troubleshooting#device-portal-file-uploaddownload-times-out until you receive the next HoloLens OS update (10.0.19041.1157 or newer, or 10.0.2048.1010 or newer).

The error is saying that your request is missing the "extract" querystring parameter. It must be present and set to "true" or "false". Set it to "true" if the file...