When I open Yahoo mail it opens in old mail so I click to change to new mail and it does but when I close mail and reopen it keeps opening up in old mail. I have looked to see if there are any settings to stop this but cannot find any. I use latest edge and latest Win10.
Have you checked your web browser for compatibility? I used to have this issue with Waterfox where it would show that browser is incompatible and wouldn't let me switch to the new version for Yahoo mail.
I updated the browser. I also tried clearing cookies. In my case I had an issue where I had to update the link of the shortcut icon with the new updated link of the mail. Then when clicking it, it will finally open on the newer version without reverting back.
Also check browser version and see if other web browsers produce the same behaviour. If it is browser specific then it is an issue with browser and Yahoo being incompatible.
You can also wait for a few days and it might resolve on its own or the people at Yahoo may fix the issue.
Edge is compatible with New Yahoo Mail, I have 2 Accounts. So is Chrome browser.
As mentioned you do need to delete some old cookies and maybe some old data, it will be renewed when logging on again.
In Edge:
3 dots > Settings > Privacy, search and services > Clear browsing data now > Choose what to clear > Probably tick the first 3 categories > Clear now.
For a more targeted approach click on the Padlock in the Address bar whilst in Yahoo Mail. From there you can also delete Cookies > Select > Remove > done, the whole lot, again these will be regenerated when logging on again hopefully minus the old data.
Where are you clicking to open Yahoo mail? Is it one of your bookmarks? If so, then it is probably set to openhttps://mail.yahoo.com/b/
The url for New mail has '/d/' in it rather than '/b/'. You can open either or both at the same time with the appropriate url. A link to just mail.yahoo.com will open it whatever your current Yahoo mail settings say you have chosen to use.
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