Minecraft Forums

First off, please don't answer with 'Get the new launcher' - I'm in the process of upgrading my computer to handle the new launcher. That said, I still have old maps that I enjoy playing, and a few friends that I've been connecting with on a 1.5.2 multi-player world.

For the past four days, when I try to log into my account, I get the message 'Cannot connect to minecraft.net'. I can play offline, but can't join my friends online. There are no issues listed at Mojang, and if I try logging into my account on a friend's machine with the new launcher, it all works fine.

Has something changed to disable logins with the old launcher?

It sounds like something may be stopping Java from connecting to the internet. What antivirus software do you have? Do you have a third-party firewall?
If you're not sure, then we can look at a log from HijackThis.
Trend Micro HijackThis is an utility that is used to collect diagnostic reports of your computer to help narrow down an issue you may be having. Download: http://sourceforge.net/projects/hjt/
Run the program, choose 'I accept', then 'Do a scan and save a log file'. After a while a text file will open. Copy everything, and paste it in spoiler tags in a reply for us to see.
How to use spoiler tags:

[SPOILER]text goes here[/SPOILER]

I use Avast Antivirus. No third-party firewall. As I said, I've been using Minecraft on this machine fine up until four days ago. I'll double-check my Avast settings, though - with the admissions over the past year or so that Java is about as secure as a wet paper bag, there's a chance that something auto-updated and mucked with the Java settings.

Okay - everything I've found regarding Java settings refers me to my browser (Firefox) settings. I've checked that configuration (on the off chance that it has anything to do with anything) and JavaScript is enabled. I've also implemented a global exception for my .minecraft folder for Avast. I suspect that it's going to take a restart before that is fully in effect.

Are you perhaps using an old version of Avast? Make sure you have Avast program version 2014.9.0.2008 (the latest at time of posting). If you have an older version, please uninstall it through Programs and Features (Add/Remove Programs in XP) in Control Panel. Then download and install the latest version: http://www.avast.com/free-antivirus-download

Update on this: I was able to fix it by uninstalling Java and then reinstalling it. Not sure why it worked, but it did. Thanks for your help!