[2022] EU4 Paradox Launcher Failure-Not a Valid Win32 Application

crofo889 said: This tmp folder does not exist in the File Manager.

To see that folder you'll need to enable View Hidden Items in File Explorer. Then delete its entire contents (NOT the folder itself!); they're only temporary files.

If however it is still not there, you can make it manually.

Good luck!  

crofo889 said: The folder referred to by the error message is never there,

You mean the C:\Windows\Installer\ folder? You did enable View Hidden Items in File Explorer?

If so, try making that folder manually.  

Aryabhata said: I'm having this exact same problem. I found this thread and attempted to create the installer folder. However the new folder never appears.

Most likely it is actually there - did you enable View Hidden Items in file explorer?

Also, check you have .NET 3.5 installed. And try these repair tools:

.NET

Microsoft .NET Framework Repair Tool is available - Microsoft Support

Describes the .NET Framework Repair Tool and how to obtain it. support.microsoft.com
SCANNOW:

Use the System File Checker tool to repair missing or corrupted system files - Microsoft Support

Describes how to use the System File Checker tool to troubleshoot missing or corrupted system files in Windows 8.1, Windows 8, Windows 7 or Windows Vista. support.microsoft.com