Installer.exe error

​@AndyBebb I agree with ​@J E L and use the Adobe Cleaner Tool. It will fix common issues, such as removing outdated Adobe software, and cleaning corrupt files such as your likely issue. Once that is done, I would make sure you also delete and empty your recycle bin can too. Now, go back to your Creative Cloud Desktop App (https://www.adobe.com/creativecloud/desktop-app.html) if you don’t have it, download it and then sign in:
 

On the left side - Apps - Manage Updates or Look for Photoshop, and click on Download. Mine is set to Open as I have the latest and greatest app ever! 
 

​@AndyBebb, it sounds like you need to repair the Creative Cloud desktop app with the Cleaner Tool. The instructions are here:

https://helpx.adobe.com/creative-cloud/apps/troubleshoot/diagnostics-repair-tools/run-creative-cloud-cleaner-tool.html

Please try that first and see if it fixes the installer.exe error.