I have been facing an issue regarding a OS X Lion installation in my Macbook Pro 13. I used to have OS X Lion, then I decided to update my O.S to the OS X Mavericks; the update was pretty good, it was successful.
The problem was when I tried to "format" my Mac, during the re-installation of the O.S, a message appeared in my screen saying that the "Recovery partition could not be created", that was weird for me, I am not very good with my Mac yet, so I tried using a OS X Lion installer (which is in a CD), I tried to install from the CD (what many people call a "clean installation") but I got the same result regarding the "partition recovery".
I saw that some of the people mention that it is needed to delete all the partitions created, but in my case, every time I try to delete any of the partitions, it says "cannot unmount disk", and I am not able to perform any deletion over the partitions as mentioned in many tutorials.
So far, I noticed that a yellow alert appears in one of the partitions before pick a drive for the installation:
Additionally, this is what I have when I open disk utility:
I tried deleting the partitions using the disk utility and even using the Terminal commands (with sudo) but I always get the same error: The disk cannot be unmounted. Please if somebody could help me, I will really appreciate, I've been without my Mac for more than 3 weeks. Thanks in advance.