John’s Background Switcher Frequently Asked Questions

Here are the most commonly asked questions about John’s Background Switcher for Windows. Click each to see the answer!

Why are background massively zoomed in on Windows 11 insider builds?

In the latest pre-release version of Windows 11 Microsoft appears to have broken the JPEG encoder that JBS uses via the .NET Framework, which results in low quality zoomed in photos being used. The latest version of JBS now has a fix so make sure you’re up to date!

Why does Windows Defender SmartScreen stop me from installing JBS?

I’ve bought a new digital certificate for code signing JBS and until enough people run it Windows Defender SmartScreen will continue to complain about it (I could pay for an Extended Validation certificate but they’re ridiculously overpriced and JBS is freeware after all). Firstly it’s nothing to worry about and secondly you’ll usually see an error dialog like this one:

You just need to click “More Info” and then “Run Anyway” to get the installer to launch. You’ll be fine from then on.

If you’re running Microsoft Edge you’ll be presented with information that JBS is uncommonly downloaded (it’s not, it just means the new certificate isn’t trusted yet) so you’ll have to tell it you want to keep it (Microsoft really want me to spend triple the amount to buy an EV certificate):

You’ll then eventually end up on the SmartScreen dialog above.

Fortunately the new certificate will last 3 years so this problem will go away for that period of time!

Does John’s Background Switcher run on Windows 11?

Yes. Yes it does.

Why do I see “Failed to switch the background: A generic error occurred in GDI+” or “Permission Denied” for ActiveBackground.jpg

Sometimes you’ll see this error when switching if you have Windows configured to sync your theme between PCs. Since this process often locks the wallpaper JBS is trying to change it means JBS is stuck and the error comes up. The simplest fix is to go to your PCs settings and in the ‘Account’ section look for ‘Sync your settings’ and set ‘Theme’ to ‘Off’.

If that doesn’t resolve your problem it’s most likely another application that is locking the wallpaper image JBS has created. If you click ‘Open Folder’ on the ‘Import / Export’ section of ‘More Settings’ you’ll see a file called ‘ActiveBackground.jpg’. If you try to delete it and you’re prevented from doing so by Windows, that’s the problem (JBS can’t either and the lower level image handling code throws the error). You can figure out what application is locking the file by installing Process Explorer and once installed doing a search for ‘ActiveBackground.jpg’ to see what application is holding a lock on it. Quite often this can be a virus scanner so excluding the folder above can be of help.

If you’re running an ASUS laptop then have a look for a process called ‘AsusOLEDShifter.exe’ – if you see it, kill it and see if that helps. If it does you won’t be the first! 😉

Why are my multiple monitor wallpapers cut off or not laid out correctly?

There are a couple of options in JBS to handle wallpapers being cut off of shown in the wrong order on multiple monitors you can try. In the ‘Advanced’ section of ‘More Settings’ there are ‘Work around multiple monitors being shown in the wrong order’ and ‘Constantly check for monitor count changes’ – the former does what you think it does so try enabling it, then switching JBS, or disabling it and switching to see what happens. The latter handles monitors being added and removed and JBS not detecting them.

Finally, Windows may simply be lying to JBS about the number and orientation of multiple monitors attached. Go to the standard Windows display preferences, select your non-primary monitor(s) and click ‘Identify’, return to your primary monitor and if there’s an ‘Apply’ button now enabled, click it. This should force Windows to get back in sync again and hopefully allow JBS to switch properly

Why does the screen flicker or my cursor jump around whenever JBS changes the background?

If right-click on your desktop and choose “Personalise”, then go to the “Colours” section and uncheck “Automatically pick an accent colour from my background” (“Accent colour” > “Manual” on Windows 11) the problem may go away. If it doesn’t, another option is to open the “Graphics” section of “Settings”:

Choose to add a “Desktop app”, then “Browse” and select the John’s Background Switcher app (from wherever you installed it) and click the “Options” button.

And choose “High Performance” then “Save”, then quit and restart JBS. I’ve had reports that can clear up any flickering. If not, let me know!

Why does the focus jump from one app when the background switches?

This is a pretty rare bug and used to effect Windows XP more than others. Basically JBS tells Windows to change the wallpaper and then during that process the focus switches away from the app you’re currently using. I used to recommend updating your graphics driver as that generally did the trick but these days it can just as easily be another app interfering with JBS (I’m looking at you Lotus Notes). If you try another background switcher and the problem goes away then let me know – but usually the problem tends to effect any switcher you use.

Do I need to uninstall JBS before installing a new version?

No you don’t! You can run the JBS installer over the top of your existing version and it’ll preserve all your settings and carry on seamlessly like before.

Why doesn’t JBS support Google or Bing Image Search any more?

Several years ago Google deprecated their free image search API but kindly left it running. Since it’s about to be switched off and its performance and reliability has greatly reduced over the years I decided to remove it from JBS completely. Since JBS is freeware I certainly can’t afford to pay for all JBS users to use it. Bing went the same way, when the free version was deprecated Microsoft simply switched it off.

Why do I keep seeing the same pictures again and again?

JBS chooses photos randomly from the photo sources you’ve given it and so it is quite possible you’ll see some pictures more often than others – that’s the nature of random selection. One thing to be mindful of is the human brain’s capacity to infer a pattern when there isn’t one – that and other cognitive biases are detailed here (it makes for interesting reading).

If you give JBS 1000 photos to choose from it’ll take on average 700 switches to show you half of them but around 7000 switches to show them all. Increase that to 10,000 photos and JBS will take around 7,000 switches to show half but around 110,000 switches to choose from all of them. Again this is how random selection works rather than being specific to JBS.

How about JBS keeps track of photos it’s shown to prevent any repeats? Well there’s a problem – while you could add a local folder of photos that never changes, web-based photo sources can change every time JBS asks for them. Say you have 100 local pictures and 100 web-based ones (the latter being a constantly changing list). First time JBS switches there’s a 1 in 2 chance you see a local picture. If JBS chooses a local one, then next time you have 99 local and 100 web-based pictures to choose from, so your odds of a local picture just went down. Keep that going and eventually you have 1 local picture and 100 web-based ones to choose from so a tiny chance you’ll see a local picture ever and JBS will look broken. Now you may say “but I only choose from local pictures, I don’t care about web-based ones”, but I have to ensure JBS behaves consistently for all photo sources and therefore is predictable.

Back when JBS used a single mode at a time and so kept track of locally shown photos to 100% guarantee no repeats I’d still get people asking me why JBS was showing the same pictures again and again. When I could prove it wasn’t. That human brain is a strange thing!

Can JBS loop sequentially through my pictures in a specific order?

I’m afraid it can’t. It used to in the distant past, but it became too confusing when web-based sources came in. It would mean each picture source behaved differently. If you need sequential switching then JBS is not the application for you – it’s all about random photos from a variety of sources.

Why doesn’t JBS support every RSS feed on the internet?

Unfortunately it can only handle RSS feeds formatted in such a way that it can get enough picture information from it. MediaRSS is the preference but it can handle some others that do embed enough information for it to parse.

Can JBS support the XYZ photo site?

The answer is it depends. If the site in question has a public API then I’d be happy to add it as a source. However if it doesn’t be aware that a lot of photo sites generate their revenue from people going there and seeing ads on them. If a 3rd party tool like JBS comes along and gets those pictures without people browsing to the site then they lose out on a lot of revenue. So I’ll only add support if the owners have provided an API and so are happy for 3rd party applications to consume their content. Otherwise I’m afraid the answer is no.

Can I tie a specific picture mode or photo set on a specific monitor?

Currently I’m afraid you can’t. But it’s on my list!

Can JBS be run as a screensaver?

It can’t as far as I’m aware. I’d love to build one but my limited free time means it’s unlikely for the foreseeable future.

I see JBS no longer works on Windows XP, do you have an older version I can install?

No, I’m afraid I can only support one version of JBS at a time. If you’re running Windows XP then you need to update your operating system or find another background switcher. Good luck!