The most secure way to get the game is to own a license through Battle.net
Old ISO files often require a valid . While many abandonware sites provide "archival" versions, the most stable way to play today is through Blizzard's modern Battle.net launcher. If you own your original CD keys, you can register them on the Blizzard website to download a modern, pre-patched installer that doesn't require ISO mounting or "No-CD" cracks. Modern Alternatives: Diablo II: Resurrected