Sometimes Yammer does weird things for some users. Which could be caused by a myriad of things. (This statement, while factual, is not helpful.)
Try this “One Weird Trick” to eliminate one possible cause for your particular problem. Sometimes it actually works.
In Internet Explorer, click the cog at the top right. Because there are so many cogs on our screen now, I gave a hint. :)
Select the second from the last choice, “Internet options”. Then, click on the Advanced tab.
Lastly, click on “Restore advanced settings.” Then Apply, then OK.
Go ahead and refresh by hitting the F5 Key.
Then, do whatever it was you were trying to do that was being weird or intermittent. See if it works. If it doesn’t, well, sorry. :( But it was worth a shot.
(Originally appeared 19 January, 2016 on the Office 365 Network)