@IT Sorry for the inconvenience this must have caused!
Error 1605 is generic error that indicates a problem occurred during the installation of the MARS agent. There can be a number of reasons why this error occurs and troubleshooting it can be challenging. Here are a few things you can try to troubleshoot and resolve these errors:
Check the installation log files: The MARS agent generates log files during the installation process. These log files can help you understand what went wrong during the installation and may provide clues about what needs to be done to fix the problem. The log files are located in the %TEMP% directory on the system where the MARS agent is being installed.
Check the system requirements: Make sure that the system where you are installing the MARS agent meets the minimum system requirements for the agent. You can find the system requirements in the MARS documentation - https://learn.microsoft.com/en-us/azure/backup/backup-support-matrix-mars-agent
Check for conflicting software: Conflicting software, such as antivirus or firewall software, can cause problems during the installation of the MARS agent. Try temporarily disabling any conflicting software to see if that resolves the error.
Repair or reinstall .NET Framework: The MARS agent requires .NET Framework to be installed on the system. If .NET Framework is not installed or is damaged, it could cause the installation to fail. Try repairing or reinstalling .NET Framework to see if that resolves the error.
Check for permissions issues: The MARS agent requires certain permissions to be installed on the system. Make sure that the account you are using to install the agent has the necessary permissions.
Check for corruption: In some cases, the installation files for the MARS agent may be corrupt. Try downloading a new copy of the installation files and using those to install the agent.
Note: Restart your computer and try to install the Microsoft Azure Recovery Services Agent again if problem persists.
Hope this helps! Please tag me in your reply if need further assistance.
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