Getting Logged out?

[sivakd]

Hi, since around 4/5pm PST Jul 16th, every time I try to submit an answer, I am getting logged out.

[hk]

There have been built in a few checks.
Use only the problempage on http://projecteuler.net. Other means are rejected.
And refresh the problem page on http://projecteuler.net before submitting an answer.

If your problem persists you can PM me, stating your configuration (browser etc) and which problem you are trying to submit an answer for.

[sivakd]

I set the network.http.sendRefererHeader to 0 for privacy reasons. Looks like this website has started checking for the referer url.

[CommodoreLXIV]

I'm having the same problem. I can't see any good reason for a referrer. If, for some reason, you're concerned about someone submitting an answer using a different web form, I'd recommend adding a <input type="hidden"> element, whose value is a hash of the username, the problem number, and a constant secret unique string.

Edit:
For firefox/iceweasel, you can get the RefControl addon. It allows you to control the refer[r]er differently for each site. Set projecteuler.net to "forge", and it will always send http://projecteuler.net/ as the referrer. This lets you submit solutions again.