Try this.. (found elsewhere)
Here are sometips how you can do it yourself and fix the Cast issues. Though few people would have got this issue resolved. thought it would be useful for the few.
Here are the Steps ---->
1) Navigate to your Desktop. (Your Desktop will be one of the default tiles on your homescreen)
2) Click on your WiFi settings on the bottom of your desktop bar (At the very bottom, right hand side of your Desktop)
3) Right click on your connected Wi-Fi network...Select 'Turn sharing on or off'
Ensure sharing is set to 'on'
I am sure this will not suffice to fix the issue...
4) Right Click on your WiFi settings on the bottom of your desktop bar...Select Open Network and Sharing Center.
5) Select Windows Firewall to the Left hand side corner of the screen.
6)Click on an app or feature through Windows Firewall (you will find this on top of the Left hand side screen)
7)Check if ChromeCast app is listed, if not Click on Allow another App and select ChromeCast app and tick it...you will see 3 type of networktypes
Domain / Private / Public
8) Check which Network Type is it (It will select by default when you tick)
9) Click on OK and now you will be back to the Windows Firewall Page.
10) Click on Advanced Settings...select Windows Firewall Properties in the Overview section
11) Now after you identified which Network Type (Domain/Private/Public), basis on this you need to select the Tab and select the dropdown option of Inbound Connection to "Allow"
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