C# can't take CPU,GPU,RAM,HDD InstallDate (f.e Win32_Processor, Win32_VideoController, Win32_PhysicalMemory, Win32_DiskDrive)

Question

I can\'t get DateTime from InstallDate - CPU, GPU, RAM, HDD. Always appears an error System.NullReferenceException, or datetime like 01.01.0001 00.00.00

This is my code w