If you did not change hardware on your computer, the problem is likely because of your virus scanner or Windows Defender removing utii.dll during a scan.
See if Windows Defender quarantined the file. You will need to restore it, and add it to exclusions.
To open Windows Defender:
Select the Start button, then select Settings > Update & Security. Select Windows Defender. Go to the History tab, make sure Quarantined items is selected at the top of the form and select View Details. If utii.dll is there, you will need to restore it, and exclude it from future scans.
If the quarantine is caused by a program other than Windows Defender, please check with that programs documentation on how to restore files, and how to exclude files or folders.
You can alternately try downloading this installer, which restores a more recent version of the DLL.
We recommend excluding the FSX\Flight One Software folder from any scans.
The official support forum for Ultimate Traffic 2 may be able to offer additional help. You can visit the forums at http://ultimatetraffic.flight1.net/forums/. Register an account there, and to gain licensed access to the forums, go to http://ultimatetraffic.flight1.net/forumreg.htm.