Explorer View uses the WebDAV protocol, which by default is limited to 50MB on the client in Windows.
You have a couple of options to deal with this limit:
- You can just download the file using HTTPS by right-clicking the file name in the web page view and choosing "Save target as..."
- If you have the necessary rights to do so, you can also make a change to your local machine's registry to increase the limit.
- Run regedit.exe
- Find the key HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/WebClient/Parameters
- Right click on the FileSizeLimitInBytes and click Modify
- Click on Decimal
- In the Value data box, type 4294967295, and then click OK. Note this sets the maximum you can download using WebDAV to 4GB per download (way more than you'll ever need).
While this gets around the issue, files in this size range (50MB to 200MB) can take a very long time to upload and download, so you should strive to keep files sizes as small as possible.