Have an empty host.
Create zabbix agent active items with keys: system.cpu.load AND|OR system.cpu.util. Update interval for example 60, doesn't matter.
Start zabbix agent on windows.
Note how these two items (or one item) become unsupported.

This happens only after agent started, i.e. only for first value which agent tries to calculate and send to server.

Not reproducible if we have more active agent checks:
If we add one more agent active item (I used some perf_counter... key) then one of items above does NOT become unsupported.
If add 2nd agent active item - both of items above do NOT become unsupported.

First comment contains debuglog example with the two items only.

Solution - add some delay at required point to postpone (for 1 second or so) first value calculation for these item keys.

Tested on agents filled in Affect version and also just in case with 2.0.4 (before ZBX-5201) - the same.