When trying to install the Arduino AVR Boards [v 1.8.8] core I get the following error message: Could not install Arduino AVR platform: Error: 13 INTERNAL: Download failed: read tcp 192.168.4.125:52425->104.18.10.21:443: wsarecv: An existing connection was forcibly closed by the remote host. I've …

Possibly the distant host was down. Try again.

I've been trying for a little while now, no luck. What else could be the issue?

When I quit and reopen the software, the following message comes up. Maybe it will help diagnose my issue Could not install Arduino AVR platform: Error: 13 INTERNAL: Download failed: remote error: tls: bad record MAC

You might need to delete a folder... see this 1.8.6 thread... Error installing platform arduino: avr@1.8.6

I don't have that folder downloaded D: nothing to delete :(

You have a different IDE version. Most internet hits cite firewall.

I found the same. I disabled my windows firewalls and tried to download but it didn't work. I'm not super familiar with this kind of thing, is there some firewall or defense system that I'm not considering?

I've just seen that what might be happening is a timeout error. Do you know how to increase the timeout threshold? I don't have access to a faster connection right now. I've also seen that mobile hotspots seem to circumvent the issue, but my hotspot doesn't seem to initiate the download

I solved the issue. I used a mobile hotspot to install the files with no issues

[image] mellyyy: increase the timeout threshold I do not know the procedure, but @ptillisch has posted it many times. [image] Putting arv 1.8.7 timeout IDE 2.x Hi @morgan777 . The installation of the "Arduino AVR Boards" platform failed due to timeout oc…

Unable to download Arduino AVR boards core

Development Tools IDE 2.x

xfpd June 21, 2026, 6:51pm 11

I do not know the procedure, but @ptillisch has posted it many times.

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Unable to download Arduino AVR boards core

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