When I am trying to upload a file via wordpress I get
Security Alert
The file you are uploading was rejected by the server.
It probably contents viruses or trojans that can damage your website
Do not attempt to upload it again as your IP address may be blocked.
I have researched and I understood is a server issue. Just that I can't contact the host, because the hosting is self-managed, so how can I make this error go away, it happens to all sites on the server. I have access to WHM and Cpanel. I want to mention that on my localhost everything works fine, file is not infected, it's a simple image, and tested several images. I understood something that i need to white list somewhere something, but wasn't specific.
Found the answer. it was because of plugin Pyxsoft Anti Malware & Security. Needed to login into WHM => Plugins => Pyxsoft Anti Malware => HTTP Inspector Tab => Enable http upload inspector - set to No.