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Login Issue Codeforces (Cloudflare Verification Loop)
By YashVashisht, history, 5 months ago, In English

Can't Login to Codeforces on One Browser Profile (Cloudflare Verification Loop)

Hi everyone,

I'm facing a strange issue with Codeforces and wanted to know if anyone has encountered this before.

Problem

Whenever I click Enter on Codeforces using my main Chrome profile, I get stuck on the Cloudflare verification page:

"Performing security verification"

The loading animation keeps spinning forever and never redirects me to the login page. I can go through whole codeforces all fine even with the same gmail, I am only facing issues while logging in.

What makes this weird

  • The same Codeforces account works perfectly in:

  • Incognito mode

  • Another browser
  • Another Chrome profile
  • Other Gmail accounts can log in from the problematic Chrome profile.
  • The issue only occurs when trying to access Codeforces normally from that specific browser profile.

Things I've already tried

  • Cleared cookies and cache
  • Removed all Codeforces site data
  • Restarted the browser
  • Restarted the computer
  • Disabled extensions
  • Allowed cookies and JavaScript
  • Logged out and back in
  • Tried different networks

Unfortunately, none of these solved the issue.

Screenshot

I have attached it below.

Questions

  1. Has anyone experienced an infinite Cloudflare verification loop on Codeforces?
  2. Is there any way to reset whatever Cloudflare/browser fingerprint is causing this?
  3. Is there a fix other than creating a completely new browser profile?

Any help would be appreciated. Thanks!

MikeMirzayanov please help, sir!

  • Vote: I like it
  • +20
  • Vote: I do not like it

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5 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Auto comment: topic has been updated by YashVashisht (previous revision, new revision, compare).

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5 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

This case seems to be rising recently!

Is there some issue?

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5 months ago, hide # |
 
Vote: I like it +16 Vote: I do not like it

To prove you are human, please arrange the lines in the correct order

for (int i = 0; i < n; i++) {
  for (int j = 0; j < n; j++) {
    for (int k = 0; k < n; k++) {
      dp[i][j] = min(dp[i][j], dp[i][k]+dp[k][j]);
    }
  }
}
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5 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Encountered this in the recent contest as well.

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5 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

MikeMirzayanov sir kindly help, this issue is not resolved yet, it has been >= 2 days and its really frustrating.

Thank you!

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5 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

I did faced this loop but had no idea how to fix. Also cloudflare is so annoying while submitting solutions.

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5 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

same issue :P

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5 months ago, hide # |
← Rev. 3  
Vote: I like it +3 Vote: I do not like it

This happens to me for a long time (1+ years).
It happens often (not always) on mobile, I'm using chrome on mobile.
Idk what causes it.

But I don't use cf on mobile anyway so I'm not bothered to fix it.

Doesn't happen on my computer.

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5 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Its main cause is desktop version in mobile . And your mobile time have to be same as the server time in Codeforces , you can turn on the features in settings of mobile.

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    7 weeks ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    Thank you so much, this fixed it for me. I was on my tablet with a keyboard connected which is probably why all pages were in desktop mode.

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7 weeks ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Most probably it is because of server. For example I use vpn for entering codeforces (cos in our country almost all websites are blocked) and I usually have problems like this. I just change server of the vpn then it works

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7 weeks ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Happens with me when i use cf on mobile(it doesn't happen always) Deleting cookies and site data always fixes the issue

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