Date Initially Written: 3 March 2005.
Problem: When trying to access a Yahoo service (i.e. Yahoo Mail, Yahoo Groups or Yahoo News), you receive the following error message:
Unable to process request at this time -- error 999
Unfortunately, we are unable to process your request at this time.
We apologize for the inconvenience. Please try again later.
Operating System: Any.
Background: This error appears to be a "catch-all" error code that Yahoo serves up when it doesn't have a more specific error code. It essentially means "Oops! Something went wrong but we don't know what, so we'll just say that Error 999 occurred."
The most common reason for receiving Yahoo Error 999 is due to some sort of bandwidth limiting system that Yahoo has put in place on their servers. Once you have exceeded your allotted bandwidth for a specific period of time Yahoo gives you this Error 999 message and doesn't allow you to access the service. People have primarily reported receiving this error when they try to access Yahoo Mail or Yahoo Groups, but other Yahoo services may also be affected.
Why has Yahoo done this? There are two reasons that I can think of:
There are many programs around that offer to automate access to various Yahoo services, i.e. check your Yahoo mailbox every 5 minutes, archive Yahoo Groups messages, download files from the Yahoo Groups Photos and Files sections, etc. If you use one of these automated tools then there is a very real possibility that you will run into the Error 999 message. Normal human usage of the Yahoo services shouldn't normally generate enough traffic to trigger the Error 999 message unless you're a very heavy user.
It appears that Yahoo uses your IP address to track the amount of traffic you're generating on Yahoo, and once you reach the limit you get blocked by the Unable to process request at this time -- error 999 message. Once triggered you will find that your IP address has been blocked for a period of time, somewhere between 2 and 24 hours usually.
Resolution Steps: I've seen many possible solutions offered to get around the Error 999 message. Many of the solutions seem rather dubious to me, but I will present them all here:
Suggestion: Clear your browser's cookies and cache (temporary files).
Chances of Working: Low. From what I can tell Yahoo isn't using cookies to remember that you've been blocked, so clearing your cookies should have no effect.
Suggestion: Log into Yahoo through a different country's server. I.e. if you usually log into Yahoo via http://login.yahoo.com/ then try http://login.korea.yahoo.com/ or http://login.europe.yahoo.com/.
Chances of Working: Low. Whenever I have tried this I log in ok but then get an error message saying Unfortunately, there is a server problem preventing access to this page. We are working on this problem, and functionality will be restored as soon as possible. Please try again in 10 minutes. This appears to be a slightly friendlier, but no more useful, version of the Error 999 message.
Suggestion: Use the "secure" option when logging into Yahoo rather than the usual "standard" mode.
Chances of Working: Medium. I have had reports that this can work when trying to get into Yahoo Mail, but I suspect it won't help with Yahoo Groups.
Suggestion: Double or multiple click on the "Sign in" button instead of single click.
Chances of Working: Low. I'm not sure what the rationale is behind this suggestion; maybe to try and confuse Yahoo while you're logging in? In my experience this doesn't work.
Suggestion: If you use a proxy server then try turning it off.
Chances of Working: Good. Because Yahoo appears to be using your IP address to track your traffic usage, switching off your proxy (or bypassing your ISP's proxy server and accessing the web directly) will result in you accessing Yahoo via a different IP address (i.e. you will be accessing Yahoo via your real IP address and not via the proxy server's IP address). Thus Yahoo will think you're a different person because you're using a different IP address.
Suggestion: If you're using a dial-up modem or some other access method that results in you using a dynamic IP address, try disconnecting from the Internet and waiting a few minutes and then reconnecting.
Chances of Working: Good. See previous suggestion for the reasons why this should work. Obviously if you've got a static IP address (i.e. you're using a cable modem) then this won't work.
Suggestion: Access your Yahoo mailbox via http://wap.oa.yahoo.com/.
Chances of Working: Good. http://wap.oa.yahoo.com/ is a WAP (Wireless Application Protocol) gateway into Yahoo which allows you to access Yahoo Mail. It's very limited but at least you should be able to view your email. Doesn't help you access Yahoo Groups or other Yahoo services though.
Suggestion: Log into Yahoo Messenger and then try accessing Yahoo.
Chances of Working: Unknown. I don't use Yahoo Messenger so I can't comment.
Suggestion: Use a different browser.
Chances of Working: Medium. I have had a report from someone that said they received the Error 999 message when trying to sign into Yahoo Mail with Internet Explorer. They switched to Firefox and the problem went away. This suggests some sort of cookie problem to me, there shouldn't be any real difference between accessing Yahoo with IE or an alternative browser, other than having different settings within the browsers.
Suggestion: Access Yahoo Mail through an email client such as Outlook Express, Eudora, etc.
Chances of Working: Good. You can pay Yahoo for their Yahoo! Mail Premium service. This allows you to access your Yahoo mailbox through Yahoo's POP3 and SMTP servers. See http://help.yahoo.com/help/us/mail/pop/ for more info.
Suggestion: If you have a web accelerator then try turning it off.
Chances of Working: Good. I've had a couple of reports from people that said turning off their web accelerators fixed the Yahoo Error 999 problem.
Why might the suggestions above that involve changing your IP address not work for some people? Possibly because your new IP address, which prior to being assigned to you may have been used by someone else that accessed Yahoo a lot, may have already been blocked by Yahoo. It is for this reason that using a proxy server to access Yahoo is a bad idea because many other people may be using the same proxy server to access Yahoo, and Yahoo will attribute all these people's traffic to the proxy server's IP address. In addition, you may actually be using a proxy without knowing it! This is called "transparent caching", where all outgoing HTTP requests are intercepted by a proxy (usually your ISP's proxy) and all responses are cached. This sort of set-up is typically used in large companies, so you may find that you can access Yahoo from home but not from work because other employees have been using Yahoo heavily.
Why might the suggestions above, that I rate as having a low probability of working, work for some people and not others? Possibly because the person inadvertently changed their IP address (i.e. They decided to clear out their cookies so they disconnected from the Internet, cleared out the cookies and then reconnected. Low and behold it worked! They then attribute clearing their cookies to fixing the problem, not realising that by disconnecting from the Internet and then reconnecting they probably received a different IP address).
Official Response From Yahoo:
Someone has reported receiving the following email from Yahoo:
The Error 999 code is a result of pirated IP addresses, and the blockage has been instituted as an Abuse safeguard. In these instances, Yahoo! has intentionally blocked these IP addresses. Yahoo! monitors all network activity and when they notice a significantly high amount of activity coming from a specific IP address or a proxy, Yahoo! blocks it. The downfall to this is that most pirated IP addresses belong to small business or home users. When Yahoo! blocks the IP address to safeguard against getting hit, the original owners of the IP addresses also get blocked.
This fits in with my theory of Yahoo monitoring traffic usage per IP address.
Another observation: It appears that being banned from one Yahoo service doesn't ban you from them all. I've been banned from Yahoo Groups but was still able to access Yahoo Mail.
Update (14 March 2005): I am 99% certain that the Error 999 when using Yahoo Groups is caused by Yahoo's bandwidth limiting. But I'm beginning to think that when using Yahoo Mail the Error 999 may also be used to signify other errors in addition to the bandwidth limiting. This is because I've received several emails from people offering solutions to the Error 999 while using Yahoo Mail and the solutions shouldn't work if the problem was only caused by bandwidth limiting (everything from changing browsers to emptying cache and cookies). So it is beginning to look like the Error 999 when using Yahoo Mail can be caused by many things in addition to bandwidth limiting, possibly something local to the user (i.e. a browser configuration setting).
Update (12 April 2005): It has been reported to me that the Error 999 can also appear when trying to access a Yahoo Geocities hosted website. Not only does this appear on sites hosted for free but also on those that have paid for their hosting. The person who reported this to me contacted Yahoo to complain and within six hours their website was back online. However he is still getting the Error 999 messages intermittently.
Update (24 June 2005): It has been reported to me that the Error 999 can also appear when trying to access the Yahoo News message boards. I've been told that the problem goes away after a while (anywhere from minutes to several hours). Also offered was the suggestion of accessing Yahoo Mail via setting up your email client (i.e. Outlook Express, Eudora, etc) to use Yahoo's POP3 and SMTP servers (only available to those people that have signed up for Yahoo's Mail Premium service).
Update (17 September 2005): Since I originally wrote this article I've received hundreds of messages from people that have encountered the Yahoo Error 999 message. I am now 100% convinced that this error is a generic catch-all error code that Yahoo spits out whenever it doesn't have a more descriptive error to provide the user. Essentially Yahoo is saying "Something has gone wrong, but I don't know what so I'll just say Error 999 and leave it at that". Bandwidth limiting is one situation that can trigger this error, but so can many other things. Because Yahoo isn't providing a more detailed error message it is extremely difficult to work out exactly what the problem is. The problem could be at Yahoo's end or the end-user's end, it could be permanent or temporary.
Update (12 October 2005): I've had a report from someone that had a web accelerator that is designed to speed up web browsing. With the accelerator turned on they were receiving the Yahoo Error 999 message, but when they turned the accelerator off the error message didn't appear. This could be due to the accelerator using a proxy server (see my notes above about proxy servers and how they can cause an Error 999).
Update (28 October 2005): I've had a report from someone that suggested something that works for them:
I had a friend with the 999 problem. It was caused whenever she cleared out cookies and temp internet files. I managed to clear using the following: when you receive the 999 message; click on the yahoo home page link on the 999 page; then click on the login link on the home page; enter your username and password as usual which will be rejected. If you then enter your username and password again it should log you in. Sounds crazy but it works.
Update (23 July 2006): Yahoo have now put up a much better error page that goes a little bit further to explain the problem. They now suggest that you scan your computer for spyware and viruses (yup, the old "blame it on a virus" excuse!), and they also say:
This problem may be due to unusual network activity coming from your Internet Service Provider. We recommend that you report this problem to them.
This answer seems to hint at the bandwidth limiting system that I talk about above, where Yahoo monitor how much traffic your IP number has used and cuts you off after a certain amount of time.
The new Error 999 page also has a link to a form that you can fill in to get help from Yahoo. Just don't hold your breath while you're waiting for a reply!
Update (22nd November 2006): I've had an email advising me that the Yahoo Error 999 can also occur when using Yahoo's 360° service. Apparantly it happens a lot when attempting to do mass deletions in the blog or of front page comments:
I have another thing to add... I have gotten this error 999 every single time I have attempted to do mass deletions on my 360 blogs. Wether it be the blogs or many front page comments. At a certain point around 40 blog posts or a few hundred front page comments it goes directly to the 999 error.
Seems that Yahoo may be employing this "error" as a way to for a "cooling off" period to members who may be trying to shut down their 360 profile. I used to do the blogging for around 7 to 12 hours per day - (addicted to it) I NEVER once got an error 999 problem from surfing and blogging for hours on end - but doing mass deletions when I was closing the blog down??? well that's when I hit the 999 error wall constantly.
Update (24th March 2007): If you get the Yahoo 999 Error when trying to upload a picture to Yahoo Profile then try the instructions found at:
http://www.yazakpro.com/chatstuff/yahoo/Solution999ErrorUploadingPicture.html
Update (4th June 2007): Several people have contacted me saying they are getting the Yahoo Error 999 on the Yahoo! Answers service. This seems to occur a lot when people try to put links in their answers, if they remove the link then the error goes away. I've done some testing and found that I can answer questions and insert links into my answers, so obviously adding links doesn't always result in an Error 999. It may have something to do with how many questions the user has answered recently, i.e. heavy users of Yahoo! Answers may see this problem more than light users.
Update (15th August 2007): Rick Gallagher contacted me and said:
I found your suggestions for handling the 999 error encountered on various Yahoo! pages. I discovered a little something involving Yahoo Answers that might help.
I used your suggestions for Answers about including links and found that removing the link worked. I went back and added a different link which was accepted. I later went back and tried to add the original link which again failed. Looking at the difference, I found that the link with the problem did not have "www" as part of the link. Adding that eliminated the error.
Update (22nd September 2007): I've been told that the Yahoo Error 999 is now occuring on the del.icio.us social bookmarking site. del.icio.us was bought by Yahoo back in 2005.
Update (3rd December 2007): I've had emails from several people saying that they are receiving the Yahoo Error 999 when they try to send email via Yahoo Mail and they include an email address within the body of the message. Some people have suggested adding extra characters on either side of the email address, i.e. you might add square brackets like this: [user@domain.com]. Could it be that this is some sort of anti-spam effort on Yahoo's part?
Update (3rd December 2007): Three people have contacted me today to say they get the Yahoo Error 999 when trying to send an email that contained a CraigsList email address. I had a look at the CraigsList discussion forums and found lots of people there talking about this problem but no definite answers. One suggestion was to removing the "remailed" line as this seemed to avoid the error.
Update (5th December 2007): A couple of people have reported that the error only occurs for them when sending from their Yahoo Mail address to a HotMail address but not to a Gmail address.
Update (6th December 2007): I've had the following reported to me regarding the Yahoo Error 999 while using Yahoo Mail:
I found that removing the "remailed to you" lines _and_ the "CRAIGSLIST ADVISORY" text immediately allowed my replies to get sent. No other emails had problems, and bandwidth usage was not an issue. Thanks for posting the info.
Update (19th February 2008): With regard to Yahoo Answers I've had a very interesting comment sent to me from MP. Seems they're having problems putting links to Wikipedia in their answers and they suggest:
It MIGHT be the case that if too many answers with the same link are given, that, because an automated system on Yahoo might think it's a form of spam, it's blocked. And obviously, wikipedia.org is mentioned in answers massively.
If that's the case, i think Yahoo's automated systems aren't finetuned correctly.
Anyway, i think the Yahoo error system should and could be more informative to normal users if that's the case.
Update (19th January 2009): I've had the following reported to me regarding the Yahoo Error 999 while using Yahoo Answers:
I have a little more on the Yahoo Error 999. I found that, in Yahoo Answers, this seems to be triggered by arbitrary content in a response. This very evening, I was posting an answer about transistors -- no links, nothing remotely evil, and got the dreaded 999 error in multiple browsers on multiple computers. My solution: try posting the first paragraph. If that works, go back and edit the response, pasting back the full reply. This seems to bypass whatever crazy bits they employ to screen the original post.
Update (2nd February 2010): I've had the following reported to me regarding the Yahoo Error 999 while using FireFox:
Using the FireFox plugin SEOquake will *quickly* make Yahoo's Site Explorer give you this error. For about the first 20 listings, SEOquake will get the site info, then get an error on the rest, and spit out that error if you reload the page or access another page on Site Explorer. I logged in to Yahoo, the error went away once, but it then quickly came back.
Recommended Reading For Yahoo Users: Yahoo! Hacks