And yet another thing to look it problems persist is how you are downloading the .iso file.
Commonly people are downloading using their browser down-loader. For most people most of the time this works just fine. If you continue to have problems or if you see a download where checksums don’t match more than once consider downloading from Konsole (or other terminal). It is an easy one command task. Also anyone with a slow or unreliable internet connection or wifi should consider doing this as a habit. This command will pause downloads and retry them unlimited times if there is any interrption in your internet connection.
$ aria2c -c -m 0 <file_to_download.iso>
To get the <file_to_download.iso> normally you right mouse click on the .iso you wish to download and select “Copy Link Location” and paste in place of the <file_to_download.iso>. So when I do the OM Lx 4.1 x86_64 .iso from SourceForge it will look like this:
$ aria2c -c -m 0 https://sourceforge.net/projects/openmandriva/files/release/4.1/OpenMandrivaLx.4.1-plasma.x86_64.iso/download
The -c Tells aria2c to resume downloads
The -m 0 option will make aria2c retry downloads for unlimited times. Some servers tend to break connection after some time. But, this option makes aria2c automatically retry when such things happen.
These options are mostly for users with slow or unreliable internet connections. If you have a reasonably fast and reliable internet connection you can just use aria2c.
There is more about downloading from command line as well as additional options to use curl and wget here.