About this Mac shows the number "135122" where it should show "OS X Yosemite"

I was experiencing the same problem with a mid-2012 13-inch Macbook Pro running Yosemite 10.10.2. Switching primary language from English to English (Canada) solved the issue. Thanks, eh.

I have the same problem with my iMac 21,5 late 2013. i changed the language to German/Austria an OSX Yosemite appeard, therefore Startvolume Macintosh HD is not displayed anymore in abaut my mac. if i turn back to German then OSX Yosemite is again 135122 but Startvolume Macintosh HD is there again.

What the **** is going on? Wanted to make a internet recovery but then mountain lion showed up and i didnt want to install ML than Yosemite.

Has anyone encounterd the same problem?

I had the same trouble after a system reboot and logging back into iCloud...

I followed andrewicloud's advice and the problem was fixed!

I changed my System Language from the local region "English UK" to the system default "English US (Computer)" and then re-set it back to UK, and the problem seems to have gone away:

Did anyone else get the problem after logging back into iCloud? Or is that just a coincidence?

Don't re-install anything - just change System Preferences / Language to English (U.K.). Use the + button if English (U.K.) is not visible.

Worked for me too, thanks. Changed it from generic English to 'English Canada' and we're all good now.

Language changed to English UK and it works, perfect

Thanks Andrew. This has bizarrely fixed the (same) issue.

Nice one thanks, fixed the problem for my MacBook as well.

It seems that there is already a security update that solves the issue. Go the App Store and you'll find that update.

May I asked a related question. I have the same vintage mba only a 13 inch model bought June 2013. Now, the question is, just below the strange numbers showing instead of OS X Yosemite, does it show, in your case, 11 inch MacBook air mid-June 2013?

the reason I am asking is that I have done an erase and install of 10.10.2 more than once and that specific info is always missing.

thanks

PIerre

I had this and found this thread by googling the issue. I solved it by simply updating to the latest version of Yosemite via the app store.