Here are some methods to troubleshoot, fix, or just survive a Opera can't save web pages with Opera, please try it out.
1.Open Chrome, then type about: plugins into the address bar and press enter.
2.Find the Java plugin and click Disable.
The windows system has a powerful feature - System File Check, it can be used to scan and repair most of system errors. In most case, your errors can be fixed by running SFC (short by System File Check), reading following tutorial to have a full scan of your system.
1.Press Win + R, type cmd, press enter.
2.Type sfc /scannow, press enter.
3.When the progress is done, close the window.
4.Restart your computer.