Compare the output with the official SHA-1 hash from Microsoft. For final RTM ISO (without updates), typical hash values are:
If you downloaded the 180-day trial ISO, you can convert it to a full licensed version without reinstalling : Windows Server 2012 R2 Datacenter Iso Download
Mainstream support for Windows Server 2012 R2 ended on October 9, 2018 . Extended support ended on October 10, 2023 . Using this OS in production without an Extended Security Update (ESU) agreement is a significant security risk. Compare the output with the official SHA-1 hash
en_windows_server_2012_r2_x64_dvd_2707946.iso Windows Server 2012 R2 Datacenter Iso Download
Always verify the file integrity. Use PowerShell (run as admin) on a clean Windows 10/11 machine:
: You can convert the evaluation version to a full retail or volume licensed version using the DISM command-line tool.