I am using KAV 2019. I am baffled and need your help. Running Windows 10 Pro build 1903. My boot drive is a 512GB Samsung 970Pro NVMe. My Windows is a legal copy (not hacked version). I noticed that starting about 2 months ago (even while running previous Windows 10 Pro 1809 build) that every day that I use the PC, about 5GB of mysterious data gets added to my hard drive. So basically at this pace, I will run out of space on my system drive (C:) in about 20 days. Upgrading to build 1903 hasn't helped. I have tried figuring out which program may be doing this but so far no luck. I have tried to do a Windows Explorer "Search" for recently used/added files 512MB+ or 1GB+ but nothing looks out of ordinary. I have cleaned out the C:\Users\AppData\ Local\Temp and C:\Windows\Temp directories but that didn't help. There must be some logging file or something likewise that is causing this behavior. I have run Malware Bytes and Kaspersky KAV virus scans (on all my drives) and they both come up with nothing. Otherwise, my system is running fast and there are no issues at all. Can someone give me some other ideas of how and what to look for?

Welcome Did you try to locate the offending files with TreeSize or WinDirStat? Please make sure Kaspersky Traces are disabled. How to Disable traces: https://support.kaspersky.com/14550#block1 Any better?

Hi. Just checked the traces and they are disabled. I am using TreeSize now to see what changes after the next few days. Thanks.

Hi Mystiky, please also check whether the folder 'C:\ProgramData\Kaspersky Lab\' contains files like 'KAV.17.0.0.225_03.16_17.13_2664.GUI0.full.dmp'. This would indicate a crash of the product.

Hi Mystiky, please also check whether the folder 'C:\ProgramData\Kaspersky Lab\' contains files like 'KAV.17.0.0.225_03.16_17.13_2664.GUI0.full.dmp'. This would indicate a crash of the product.

Checked there and nothing. I think it's one of those Fornite / Streaming games that the kids use. We shall see in a few days.

Hello Mystiky, As well as the information/guidance provided by richbuff & Schulte, are any KAV automatic (Full/Quick) scans running and expansion drives being attached to the system, which KAV will start to scan, at the same time? Please let us know? Thank you.

None of this is Kaspersky related, I am 99.9% now sure. Will re run TreeSize on Firday and things will be even more clear.

The culprit was System Restore! I changed it to only use 15GB and immediately I got almost 15GB back. Thank you everyone!