Did you add the NuGet package? System.Diagnostics.EventLog

You may also need to change the target framework to net6.0-windows.

I didn't know about that, ty I will try it

yes it worked, tysm. VS didn't suggest NuGet package and couldn't find about it in MCS docs either so were a bit confused

How I figured it out was looking at it on https://docs.microsoft.com/en-us/dotnet/api/system.diagnostics.eventlog?view=dotnet-plat-ext-6.0

If it's part of the Platform Extensions, you get it via NuGet. Usually it's named the same as the "Assembly" up top.

so if its Extension it's always part of NuGet package?

AFAIK, yes. At least you should suspect it.

got it, thank you