Is It Alright To Run Both Windows Defender’s And Kaspersky Internet Security’s Real-Instant Protection Together At The Same Time?
You should not be able to run both at once. Defender is designed to walk itself off if it detects another anti-disease. This would smack of to me that Kaspersky is not installed correctly or has become corrupted.
Try a reinstall of Kaspersky, or remove it it – your choice.
(An afterthought – is the Kaspersky payment up to date?)