When a partition (/dev/sda2) that contains the previous install was selected for this new installation (after setting the type-ext4 and mountpoint to /) the next window said the following
'The file system on /dev/sda2 assigned to / has not been marked for formatting. Directories containing system files (/etc, /lib, /usr, /var, ...) that already exist under any defined mountpoint will be deleted during the install.
Just to make it clear,
When a partition (/dev/sda2) that contains the previous install was selected for this new installation (after setting the type-ext4 and mountpoint to /) the next window said the following
'The file system on /dev/sda2 assigned to / has not been marked for formatting. Directories containing system files (/etc, /lib, /usr, /var, ...) that already exist under any defined mountpoint will be deleted during the install.
..'