i'm trying to install Yosemite but I could not select the HD of my MacBook to install it as it told me that "This disk is used for time machine backups". After reading https://support.apple.com/en-us/HT203322
I moved the backups-file from the root directory to the trash, but then it told me "OS X cannot be installed on "Macintosh HD". Then I tried to resize my partition according to https://support.apple.com/en-us/HT203482
, but this is not possible as the blue portion of my partition is too big (but maybe I didn't quite get how to do this). Do I have a disk space problem?