Before saying this is another duplicate question, it is not.
So I'm coding an application which needs full admin rights and until here is all good, I can do it without problems by editing the manifest and setting it as requireAdministrator.
Now.. the problem is this: my application starts at startup so every time UAC pops up. I noticed that antivirus softwares for example require admin rights only the first time not always every reboot of system.
So.. is it possible to make the application display the UAC only when opening it first time, not always?
I think you've missed the point of UAC. A process triggers a UAC prompt when it indicates it needs admin privileges, for example to install an application or modify system files. So if your app doesn't constantly need admin privileges, then don't have it ask for them. Separate the bits out that need admin privileges into separate components.