Using an out-of-date version of Windows 7: Make sure your installation of Windows 7 is completely updated with all service packs and updates. Older operating systems can occasionally cause compatibility problems with specific programme elements.
Unsupported.NET Framework Version: Windows 7 does not officially support the version of the.NET Framework that Repetier Host may need. For Windows 7 compatibility, check Repetier Host's system requirements.
Installer corruption: There's a chance the Repetier Host installer you downloaded is flawed. To rule out this possibility, try downloading the installer once more from the official website.
Ensure that you have administrator rights on your Windows 7 computer. To ensure you have the required permissions, right-click the installer and choose "Run as administrator."
Disable any firewall or antivirus software that may be interfering temporarily on your Windows 7 PC. These security technologies may have a negative impact on the installation procedure.
Hope it will help you.