opera_autoupdate.exe is a program which is most likely legit. So, if opera_autoupdate.exe is on your PC, it is most likely ok, and will NOT be a cause for concern. Even if your PC is virus-free, it is still recommended to purchase a well-known antivirus with a good track record, in order to defend your PC against viruses and malware.
This application is usually stored in C:\Program Files (x86)\Opera\42.0.2393.94\opera_autoupdate.exe.
The MD5 checksum for this file is 2e852b20e2bbe53b2e16630ac141d3b9.
This program is NOT a Windows service. This is good.
This exe runs in 32-bit mode. It can not exploit the full power of current PC chips. This is quite normal because the authors did not bother to upgrade it to 64-bit code.
The description present in the file is Opera auto-updater.
File version extracted from the file 42.0.2393.94.
Author Opera Software.
Copyright notice Copyright Opera Software 2016.
opera_autoupdate.exe has a digital signature. Today the large majority of clean programs are digitally signed.
The digital signature attached to opera_autoupdate.exe verifies as ok. This is very good.
Digitally signed by: Opera Software AS
Certificate's issuer name: DigiCert EV Code Signing CA (SHA2)
It has an uninstall routine, which is good. si are uninstall.