Error whilst downloading mods: An unexpected error occurred on a send.

[economicmar]

In the thunderstore app, the download feature doesn't function any more

The computer connects to the website fine and the loader has an exemption to the firewall

a reinstallation has been preformed

[MythicManiac]

This generally means that something is preventing your connection to the downloads CDN. While I can't say why that is in your case, the workaround that usually works is to connect through some other network than what you were using when you got the error, such as a VPN or sharing your mobile network.

Workarounds aside, we're also working on making the mod manager support several download sources rather than just one, which should allow it to function as long as you can connect to at least one of them.