I have a problem installing Zorin Linux on my laptop

Installing Zorin OS
2

Hello Merlin, welcome to the forum.

Despite of this message, you can rest assured that Windows is/will be on your c:\ drive. You can assume this is a bug where the installer doesn't detect the Windows OS during the installation. There are many others including me also have faced it too. But don't worry about it, you can still proceed with the Zorin installation.

You should proceed with the Something else option and select your 50gb partition and format it as ext4 and choose the mount point /

Then proceed the installation. If it gives the warning no efi partition then you can ignore it, as this is not required under legacy BIOS MBR mode.

Since you want to install Zorin on a separate drive, the best option for you to go with the "Erase disk" option. When you continue with this option the next interface will show to choose the drive where you want to install Zorin. From the drop down menu select your F:\ drive and proceed with rest of the installation process.

You can look at the following video tutorial to get a more clear view of the installation process with Erase disk option. https://youtu.be/0s2RSfNWut4?t=23m30s

Also check: Before you install