The website "ad.doubleclick.net" requires a client certificate when I open Safari. What does this mean? It gives me 3 certificates to choose from.

I got this today as well with the 3 certificates to choose from. Two of them started with com.apple.idms.appleid.prd. One expires in 4 days and the other one in 2017. Otherwise they are identical so I think this is where Safari gets confused. I went into Keychain and deleted the one that expires in 4 days by searching for it under "All Items". I closed Safari and right clicked on the Dock Icon as well to Quit. I opened Safari and the next time I got the popup I selected the one certficate left for com.apple.idms. So far so good.

This could be an issue with corrupt certificates that are being stored in Keychain Access. The corrupt ones are the ones listed in that dialog box that says "The website ad.doubleclick.net" requires a client certificate. The fix:

1. Open Keychain Access (open Finder, then go to the Applications > Utilities folder, Keychain Access is in the Utilities folder).
2. In Keychain Access search for all of the certificates that are listed in Safari dialog that tells you "This client requires a certificate".
3. When you find those particular certificates, select them and then DELETE those specific certificates out of Keychain Access.
4. Restart Safari.

Hope this helps.

I was getting prompted for a client certificate for ad.doubleclick.net whenever I visited youtube.com using Safari.

I managed to get rid of the problem by blocking ad.doubleclick.net. Here's how you can do the same:

1. Open the file '/etc/hosts/' in your favourite text editor.

2. Add the following text on a new line: '0.0.0.0 ad.doubleclick.net'

3. Save the file

You will be prompted for your administrator password when you open and save the file. Test the result by reloading a problem page in Safari. It should take effect immediately.

I hope this solves the problem for you too.

Folks who are up on this problem have suggested on other threads that this is double-click's problem, not yours. Double-click has mis-configured their server settings.

It is therefore not appropriate to delete any of YOUR certificates, or take any other action on your part. This is likely to be their problem, and they will eventually fix it.

Force quit Safari. Press and hold the shift key when starting up Safari again. Let us know if this stops the behavior you are seeing.

You can still use the helpful answer in safari as well as chrome. Some of which you can use on the Iphone. Also you could go into the preferences on safari and settings in chrome and disable extensions. If the pop up now does not come back, then it's one of the extensions You can turn them off one at a time till you find the one causing it and delete it.

When you reopen safari go to safari preferences and delete history and caches. In safari privacy block third party cookies and remove all website data.

SMBW wrote:

Hi BobTheFisherman, I did as you suggested and it happened once more but seems to have stopped for now. We will see. Any idea why that just started happening? Thank you for your response.

At some time before it started happening you visited a site that created the error, for whatever reason. Force quitting Safari and restarting with the shift key pressed prevented Safari from opening previously visited sites, including the site that produced the error message.

Do you have any idea why this just started happening?

Yes.

somebody thought of a new way to try to SCAM Users.

ad.doubleclick.net is an entity that tracks you and aggregates your internet use to send you focused advertising on web pages.

>> Do not download anything!! if it gets downloaded anyway, do not Install!

Certificates in keychain that are not valid, out of date or not trusted will have a red circle with an X in it. All others should be left alone.

I've worked at three separate client offices today. This is appearing on all Macs when visiting a website that has ads or tracking by ad.doubleclick.net. Obviously something has changed with their tracking and I hope they get it fixed soon.

I think this is more than a safari issue. I suddenly started getting this as well this afternoon. I get it in Safari and Chrome on my Mac and I also have it happening on my iPhone.

I'm having the same issues.. I'm using chrome now instead of safari and it seems to be working fine... Of course its finals week at school so I cant really take my computer in to get fixed..