Here are some things that might help depending on your system. The info for 10 is toward the end. I've added FYI for 11 just in case it might help with IE 10 and your system. Also, double check that you still have 10, it may have automatically updated to 11.
I haven't found any support for IE 11 and the Yahoo Calendar on Yahoo. Here is what I have found with the computers I use, one with 8.1 and IE 11 and one with windows 7 and IE 11.
If you are using Windows 8.1 with IE 11 the calendar will not work. If you are using Windows 7 with IE 11 go to the gear icon, click on compatibility view and add yahoo. Make sure and uncheck the use Microsoft list and the view intranet sites in compatibility view. Close out of everything and then try. Otherwise, you can try Firefox or Chrome. At least this is what has worked for me.
Added note, if you do this for Windows 7 and IE 11 the My Yahoo Homepage will not load mail or calendar modules. It is a one or the other type thing for Yahoo, windows 7 and IE 11. Although just recently the mail and calendar modules loaded on the home page.
If you are using IE 10, besides the above, please make sure the Enhanced Protection mode is unchecked in internet options, advanced tab.
I also have Foxfire and Chrome and the calendar does work. It would help to have more information as to what you have and what you have tried if you still cannot access it.
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Here are some things that might help depending on your system. The info for 10 is toward the end. I've added FYI for 11 just in case it might help with IE 10 and your system. Also, double check that you still have 10, it may have automatically updated to 11.
I haven't found any support for IE 11 and the Yahoo Calendar on Yahoo. Here is what I have found with the computers I use, one with 8.1 and IE 11 and one with windows 7 and IE 11.
If you are using Windows 8.1 with IE 11 the calendar will not work. If you are using Windows 7 with IE 11 go to the gear icon, click on compatibility view and add yahoo. Make sure and uncheck the use Microsoft list and the view intranet sites in compatibility view. Close out of everything and then try. Otherwise, you can try Firefox or Chrome. At least this is what has worked for me.
Added note, if you do this for Windows 7 and IE 11 the My Yahoo Homepage will not load mail or calendar modules. It is a one or the other type thing for Yahoo, windows 7 and IE 11. Although just recently the mail and calendar modules loaded on the home page.
If you are using IE 10, besides the above, please make sure the Enhanced Protection mode is unchecked in internet options, advanced tab.
I also have Foxfire and Chrome and the calendar does work. It would help to have more information as to what you have and what you have tried if you still cannot access it.
I hope something works for you.
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