How are you attempting it?
For me, and I am sure this is standard, I just right click in the middle of the page and "Add to favorites"? I have my favorites categorised into groups and select which group I wish to add to.
Ok. I had a poke around Microsoft pages on this. It seems you have probably deleted your "Links" folder, so the favorites have nowhere to go. This is there reccomendation.
Create a folder in your document (C:\Users\YourUsername) called Links, then restart your computer. the problem has been caused by accidentally deleting this (Links) folder and the system no longer has anywhere to save the favorites.
I looked at both users and the Links folder was there for both. I delited the one under my account and created a new one and then restarted, no luck. I logged into the other account and can bookmark pages with no problem. I then copied the files in the Links folder that works and entered them in the Links folder under my account, again no luck. The only new program added recently was Auslogics Boostspeed, which reported numerous problems, which were fixed. If I don't solve this by days end, I will likely look for restore point before it quit working. BTW, I have also tried going back to IE 8, with no luck.
Navigate to the Web page which you want to add to your Favorites. Next, click on the "star" menu button, located in the upper right hand corner of your browser window.
The Favorites drop-down interface should now be displayed. Click on the option labeled Add to favorites... as shown in the screenshot below;
The Add a Favorite dialog window should now be displayed, overlaying your browser window. In the field labeled Name you will see the default name for the current favorite. In the example above, this is "about.com Need. Know. Accomplish." This field is editable and can be changed to anything that you desire.
Below the Name field is a drop-down menu labeled Create in:. The default location selected here is Favorites. If this location is kept, this favorite will be saved at the root level of the Favorites folder. If you wish to save this favorite in another location, click the arrow within the drop-down menu.
Continue with page 5 @http://browsers.about.com/od/internetexplorertutorials/ss/add-to-favorites-ie9.htm
That is the problem, nothing happens when I click on the "Add to Favorites" button. The pop up does not come up. Is it possible the pop up blocker is not allowing this? I will try turning it off to see...That did not help either.
Somehow, by messing with a spare installation, I managed to simulate this fault. It certainly does have a connection with the "Links"
I removed the Links. When I logged on I log on and opened a page, then immediately tried "and add it to favorites", it worked. As soon as I had multiple tabs, it stopped again.
I moved the 'Links' folder from the "username" folder, to a safe place, together with copying my favorites to the same place. and then, when I tried an immediate 'Add to Favorites", a new Favorites Bar folder was created. I copied all the items from the old 'Links' and favorites folder, and everything was working.
P.S. This may be important! I found, by default, a Links folder actually in the Favorites folder.I deleted this also.
I removed Favorites and Links folders, and restarted IE. It came up with an empty Favorites folder, but still would not let me add pages. I have restored both file and am back where I started. The soga continues.
I missed a point in the earlier posts. You have two accounts? You could create new account, simialrly named to the one which is giving the problems, For example, if the bad one is called Wayne, create another called Wayne1. If it works,when you are satisfied you have transferred everything worthwhile, delete the offender.