Try a restart of SolidWorks or the machine and check.
I am not sure but I think if you open an older, say, 2006 file it won't be there, so maybe save it as a 2012 and reopen it?
No luck so far, I restart every morning, and it has not been working for a while.
This file was created in 2012, and even starting a new file, I do not get a freeze bar.
My VAR suggested an install "repair" which did not do it. Next they want the registry reset. I don't want to mess with this, and will wait fo IT to do it.
What service pack of Solidworks are you running, I had some problems with the freeze bar in SP1 when it came to some files converted from 2011, My VAR sent my file to SolidWorks and they came back saying that problem was fixed in SP2 or SP3 I cannot remember which, so I just had to wait but it worked ok on all new parts and some smaller parts converted from 2011.
If you right click on the freeze bar can you choose "roll to end" to roll the bar to the bottom of the feature tree, if this works you can right click on the bar again when it is at the bottom and click roll to top.