UPDATE 30 Dec 2019: After visiting family and finding they had the same issue with random characters in the save dialog box, I realised the only common software we had on our systems other than the Windows 10 operating system was Sophos Home Premium. I dug around the settings a little bit and found an option which solved the problem (see below).
For anyone looking to really dig in to Windows 10, I’d recommend one of the Windows 10 Advanced guides.
To find and disable this option, double click the Sophos icon in your system tray and click Settings:
When the settings page has loaded in your web browser, on your dashboard click Protection then cick Web and then clock Advanced Settings under the Safe Online Banking section:
When the box expands, click the right hand circle next to the Protect Against Keyloggers option (it wlll turn red):
About 6 months ago I started experiencing one of the most bizarre problems I’ve encountered in my 25 years in IT.
With no rhyme or reason nor predictable trigger that I could see, sometimes when my computer boots up, the keyboard types random characters.
This occurs immediately upon boot-up meaning that I cannot even enter my password at the login screen with the physical keyboard, I have to use the on-screen keyboard (which works perfectly).
I also then discovered that after using the computer with no problems, I would attempt to save a file and the same thing would occur when trying to enter a filename in the save dialog box.
At the time of writing, I don’t have a fix but I thought I’d write a post of the situation in the hopes it will provide a focus point for others having the same issue.
So here’s what I’ve discovered:
- It’s not a weird character mapping issue or other keyboard layout that’s kicked in, I know this because pressing the same key twice gives a different character.
- Re-enforcing the point above, if I type the 26 characters of the alphabet, many characters are repeated (and obviously many ommitted).
- The problem occurs randomly, probably 1 in 10 boot-ups.
- Sometimes simply rebooting clears the problem.
- The problem isn’t isolated to the login box, it occurs on any input (tested by trying to enter wifi passwords prior to logging in).
- The problem occurs on my laptop with the built-in keyboard and also when I use a docking station and USB external keyboard.
- If I click the accessbility icon and use the on-screen keyboard to login, that works fine.
- If I login successfully (using the on-screen keyboard), my keyboard starts working again once I’m in.
- The problem has spanned multiple major Windows 10 version upgrades.
- I’ve had this laptop for 5+ years, it has had various flavours of Linux, Windows 7 and Windows 8 installed, none of which have had the problem.
I saw a post saying that Shift + Alt may solve the problem, at the time of writing I haven’t had the chance to test this but will next time it occurs!