Trying to get rid of error "The startup disk cannot be partitioned or restored to a single partition". Recovery HD visible.

Question

Hello,
I've been stuck for some hours now trying different things to install Windows 7 on my Macbook Air, and I think now is the time to call for some custom help.
I'm using OS X 10.9.5 Mavericks.
So some months ago I just wanted to run Linux on my laptop so I installed rEFInd, shrunk the Macintosh HD partition by 25GB and booted on a linux live USB flash I burned using dd.
Then I used gparted to create my linux partitions.
It worked just fine, even though disk utility from OS X seemed quite unhappy about this (it seemed to have incorrect informations about the filesystem on these partitions, seeing them as journaled Mac OS while they were clearly not). At this point already, the Recovery HD from mac showed up in disk utility, which I found weird but didn't bother me.
But recently I needed windows on my Mac. So after a few tries for the triple boot, I managed to create a bootable USB stick with boot camp, which already showed me the message "The startup disk cannot be partitioned or restored to a single partition" and hence refused to partition/install himself.
So I thought "OK, that's no big issue, I can just partition with disk utility and then boot on the USB stick and everything will work fine". But when EFI booting on the USB flash drive I got stuck at the beginning of Windows installer with no keyboard or mouse support.
After some hours spent googling, I was unable to find a working fix for that, and as there was no support for my case (where I used bootcamp to create the bootable flash but NOT to partition/reboot) I decided to give bootcamp a try.
So I erased my linux partitions, and cleaned up everything I could on the HD with disk utility. That means I now have two partitions showing in disk utility : Macintosh HD and Recovery HD.
When using disk utility from terminal, the list is :
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *121.3 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            80.0 GB    disk0s2
   3:                  Apple_HFS Recovery HD             650.1 MB   disk0s3
But boot camp still isn't happy, and the message "The startup disk cannot be partitioned or restored to a single partition" keeps popping after the intro and I can't partition/boot from bootcamp.
So, as I don't understand what is wrong here anymore, any help would be greatly appreciated!
I will be watching the thread a lot because I really would like this resolved (or windows installed one way or another) this weekend; so any questions on my past manipulations or config just ask!
Thank you.

Answer 1

keyboard issues are also something of a common issue.
I wish the best threads were voted to the top of forums, something! Me, I literally burned out here, but after installing 10 Preview, wanted to "see what was going on" after hiatus of a couple years and see if anything had changed (no, not really!)
Also, these new Communities are not putting "more like this" and failing to help too.
I think rewriting Boot Camp Assistant's built in help and pdf would help a lot, and needs to be clearer and go into details. And Yosemite was not it seems tested against Boot Camp, and drivers for new Macs + new OS also lag behind. Again, common and no sign of improvement or change.
One of the tricks to the "can't partition" is rather simple - of course backup is step #1 and is spelled out - SHRINK the main HFS+ partition! then stretch it back to full length. Sometimes a reboot is needed, and sometimes even do a Safe Boot - not sure what but Recovry Mode might be a good option too. That does seem to consolidate free space, move files that are locked and cannot be moved otherwise, and allow BCA to partition, jusst be sure to have enough space left and large enough for a proper Windows install (and fudge factor).