Avoid websites claiming to offer "free retail keys" or "cracked" versions (like "v9.0.42.0"). These downloads often contain or scripts that can take over your machine with elevated privileges once the MSI is run.
If you require the Professional version for commercial use to remove the branding or access advanced elevation controls, you can purchase a perpetual license: MSI Wrapper : Approximately $198.00 for a single-user license. msi wrapper pro v90420 retail license key free