If you read that red message in the background you’ll see that UrBackup server complains about F:\UrBackup not being excluded from on-access virus scanning. To check that it writes a virus test file (that’s why it says Test_File in the virus description https://en.wikipedia.org/wiki/EICAR_test_file).
So you should exclude at least F:\Urbackup\urbackup_tmp_files from on-access scanning.