This question may seem repeated but I have other more issues. I installed 8.1 in my dell 5537 and dual booted it with ubuntu 14.04..I worked well..I installed with alongside windows option..It took 30gb(as I selected the space) space from my logical drive which was last drive...I have four partitions c:,D:,E:,F:(or local drives). Now I deleted the ubuntu from disk management(as there was some problem in ubuntu and i could not fix it).I fixed the windows MBR with live CD. I now want to dual boot ubuntu 15.04 again..I have changed boot mode to UEFI(with secure mode disabled) I get grub to install ubuntu. I clicked install ubuntu. Now i get the Message of
"force UEFI installation?...this machine's firm ware has started the installer in UEFI modebut it looks like there may exist operating systems already installed using "BIOS compatibility mode"...If you wish to install in UEFI mode and dont care about keeping the ability to boot one of the existing system,you have the option to force that here......".
Now if i force UEFI i cannot see any of my partitions of windows and see my whole disk as 500gb disk(as /dev/sda ntfs) and no option of new partition table or other disk...It will erase my whole disk.....I have already shrinked volume from C: and divided that space into 3 part (one primary and active ,two logical).
I use mostly windows and don't want to lose any data from any disk and volumes.. I am not familiar with linux much...So please help with detailed steps...