Some computer viruses evade the surveillance of security software. But some clues and strange behaviors can betray their presence, such as strange accents in texts.
Malware often tries to be invisible to users. But the developers of these programs are like everyone else, and sometimes they make mistakes that lead to bugs that can reveal the presence of an infection. Changing the default search engine of your web browser, the untimely appearance of PowerShell windows or excessive use of PC resources for no apparent reason are well-known signs that should alert you.
But another strange behavior, which could pass for a simple bug, also most certainly indicates the presence of a malicious program on your computer. Spotted for several years by members of the How It Works Security Forumit even seems to be becoming more and more frequent.
This problem that should alert you is that of double circumflex accents or umlauts. When you are writing a text, no matter with which application, and you try to write characters like ê or ï, your PC then displays a ^^ or a ¨¨, without giving you time to enter the accented letter.
Faced with this strange malfunction, you probably think that there is a problem with your keyboard or Windows. However, there is a good chance that neither one nor the other is the cause, and that a malware in the first place. So there is no need to rush into buying a new keyboard or completely resetting your PC.
The double accents bug is probably the result of an infection on your PC that “is characterized by a scheduled task that points to an exotically named DLL or a legitimately named executable,” as explained by bazfile, moderator on the CCM Security Forum. This behavior allows the malware to slip under the radar of many antiviruses.
To try to resolve the problem and remove the infection, start by running a scan with security software like Malwarebytes (free). And if the problem of double circumflex accents or umlauts persists, then take a look at the How It Works Security Forum in order to request help.
You will probably be asked to use the free FRST software to generate reports, then share them on the forum so that members can analyze them, and possibly offer you automatic repair scripts for your PC. In any case, the important thing is not to let the infection linger on your computer, at the risk of having sensitive data stolen!