I don't understand why your antivirus keeps reporting this as malware. It claims it's a trojan and points to a specific file location. When you start your computer, it alerts you about a threat and adds it to the virus database, but you can't locate the file in the directory. Would deleting that folder be a good idea, since it seems to be a necessary Windows 7 file?
Malwarebytes performs a full scan. After completion, you can remove it if desired: https://www.malwarebytes.org/
I would use Malwarebytes to check, but if nothing appears, you might need to search for the infection yourself. One approach is to download Process Explorer and check if anything unusual runs under your main Explorer process. You can also explore %temp% and %appdata% folders for suspicious executables. Additionally, open the Run dialog and go to HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunHKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce. This will let you review any "fishy" programs launching at startup under those keys.