Does Windows 10 update turn F-Secure IS off?

Hello,

Sorry for my reply and suggestions!

For me it sounds like "overload" under system. With high CPU/drive/network usage by different software at system-background. As result - F-Secure (own design) or maybe system just goes to be with "broken ability" do the checks about "validation status of its" (temporary). Like if there start be delay with some "own processes" and F-Secure start to think that there something wrong with installation/state - so required "trigger/prompt" about it; If you do not do anything - status maybe switched to OK (in your situation - when all updates installed);

I had such experience with a lot of my outdated machines (512Mb RAM, 1.00 Ghz; and related configuration); And generally it was only with F-Secure IS installed (except browsers and some media tools);

If I used it not daily - with much more trouble-result (since there also can be notification that "databases outdated"); With Windows 10 there can be something with much more impact (where updates comes automatically and with my experience take more "resources"); Also - I not sure about your machine-configuration (if there enough CPU/RAM resources to feel good while there high usage of them);

I think you also able to create fsdiag (by F-Secure Support Tool) after such situation. And will contact F-Secure Support. Maybe they able to re-check it (since - your machine with abilities to work with Windows 10 and current F-Secure IS - so it should be valid support request);

What about "Is that something similar Kaspersky reported Windows doing to their software?":

If I normally understand your ask -> I think - not; because with my understanding there more valid meanings that software (there - OS), which unexpectedly break user's systems or block/break/prevent another "valid" software for proper work - more looks like "malicious/harmful"-activities; Things like BSODs, crashes and some other situations most likely unwanted for users. Usually security software designed to protect user's systems against "harm it" (when it possible); And when some of system updates or changes will 'randomly' break security features (or just features) under security software (or just software) --> there not large difference if there "malware"-impact;

But I think that most of such situations based on "undocumented" and not-proper-hack-tricks under such software. With my understanding - F-Secure will drop or re-designed many own features for preventing any compatible troubles with system. And with most of things they trying to perform "proper Windows guide-style" in most of meanings;

// and it also generally should be about update to Windows 10 (from previous OS or build);

while your situation - if I normally understand - mostly about "Windows updates each month"; If not - there quite likely that such large update/upgrade will "break" some software. But with my experience -> Windows 10 with more good design about it. And with update to recent Creators Update - my FS Protection properly worked after it (F-Secure IS/SAFE beta technology preview); But I can to suspect that some of previous F-Secure builds (versions) will be with troubles; Also I can to expect that such design valid for most of large (or well-known) security software companies;