If you are experiencing the "Unable to read launcher metadata from any source" error, there are a few steps you can take to fix it.

The first thing you should do is to make sure that the Modrinth App is able to access the Modrinth servers. You can do this by opening the following links in your browser's incognito / private window and make sure they load without any issues:

If any of the links do not load or show an error page, this could be the cause of the error. If you encounter a Cloudflare page similar to the one shown in the screenshot below, this is also considered an issue. The App cannot complete the challenge presented by Cloudflare, which is why the error occurs.

The detect.txt link should be an empty page, while the other links should display machine-readable gibberish. If you see any other content on these pages, it could indicate a problem.

If you are using a VPN, especially a free one, try turning it off and see if that helps. Sometimes, using a VPN can trigger the Cloudflare challenge page. On the other hand, if you are not using a VPN, try using one. Your IP address may have been associated with some malicious activity, which is common for ISPs that use NAT or dynamic (rolling) IPs. If this is the case, the issue should resolve on its own once your IP changes.

If all the links above open without any issues, but the error still persists, it is possible that something is monitoring your internet connection and dropping Modrinth's requests. This could be caused by a third-party antivirus software or a firewall.

To troubleshoot this, try temporarily turning off your third-party antivirus software. If you are using Microsoft Defender, you do not need to turn it off as it does not cause this issue. If turning off your antivirus software resolves the error, you may need to add an exception for Modrinth in your antivirus settings.

In some cases, a country-level censorship system can also cause this error. Use a system-level VPN service when opening the Modrinth App if you suspect this might be the case.

If none of these solutions work, it is best to open a support thread. Explain everything you have tried so far, and we will be able to assist you further.