markonikolic

HI @agueritz,

​I am very sorry to hear about the issues you are facing.

It looks like you use an old BackWPUp version – v5.6.6. The latest stable version is v5.7.2

This particular section was updated in v5.6.9 to prioritize wp_is_valid_utf8() – Github link

The solution is to update BackWPUp to the latest version which should solve the problem.

Would you be able to try this and let me know if that helped?

Thanks!

Thank you, @lindt01

It seems like updating to v5.6.8 of BackWPUp resolves the problem, so leaving the information here in case someone else jumps in to see the details.

Best Regards

Hey @daq123,

Sorry to hear about your experience with Imagify.

There is a way to reduce a server space using it with a minimal adjustments in the settings:

1. You can disable Backup of original images so they would not be stored on your server after compression
2. You can disable NextGen images creation so WebP/AVIF version would not be created on top of the original format image

Few things to note, that should be useful:

• We still can not delete original format of image (compressed one) once WebP/AVIF is created as it might be needed to ensure compatibility with browsers that still does not support it and for being able to regenerate if needed
• Please have in mind that WordPress will also do some actions that is out of Imagify control. For example, if you upload image that is wider/taller than 2536px, WordPress will keep that large image, and on top of it will create the -scaled one that is 2536px. Additionally, it will create two new thumbnails of 2048px and 1536px. To avoid this, you can use Disable “BIG Image” Threshold plugin.

Hope this helps. Feel free to share any additional information about your concerns and we will do our best to help.

Best Regards

Hi @tslarkin ,

Thank you once again for the detailed report as it was very helpful in identifying the issue!

We’ve confirmed the issue on our end as well. Files with apostrophes in their names cause backups to fail with the “File name cannot be empty” warning in v5.6.6 and v5.6.7.

Interestingly, versions prior to v5.6.6 didn’t error out, but silently skipped the entire folder containing the problematic file.

It would be great if you could check your previous backups and confirm if folders that contain problematic files were included in the backup?

We’re actively working on a fix. In the meantime, the workaround is to rename any files containing apostrophes.

Best Regards

Hi @aga2442,

Marko from Imagify is here.

There are some factors that could cause the process to fail. The theme switching itself should not be the direct reason for this, and it would be good to do a basic troubleshooting and see what might go wrong.

To do this, please check this guide and let me know if you find anything helpful – https://imagify.io/documentation/optimization-is-stuck/

Feel free to let me know what you found.

Best Regards

Hey @goglobal2016

Thanks for sharing this.

You can activate WebP/AVIF in Imagify Settings (WebP creation is on by default) – https://imagify.io/documentation/enable-webp-images-works/

I was able to optimize some of these, this one is 49kB after optimization in WP plugin https://www.markonikolic.net/wp-content/uploads/2025/04/img-20250313-wa0005.jpg

And this one is (I use AVIF conversion) also around 50kB after compression and conversion (original format is well done) https://www.markonikolic.net/wp-content/uploads/2025/04/img-20250313-wa0002.jpg.avif

So, it would be best to focus on optimization process, once we resolve this, you can simply use WebP/AVIF as it should be quite good.

The problem with optimization seem to be related to the server configuration or firewall settings. But this is not block to our server, but to self-request (Admin AJAX in this case). It would be good to check security plugins and also to contact your host in order to see if you use any rule to disable/limit Admin AJAX calls (it could be performance plugin as well).

​Let me know if you need any further advice, I am happy to help.

Best Regards
Marko

Hi @goglobal2016

The process depends on many factors. Usually, when image is not optimized and you get Well done... message, that means further compression would affect image quality and we stop the process.

Based on information you provided, I would focus on the following points:

• Did you convert images to WebP/AVIF? If so, what is the gain of that format?
• Do you optimize images using Smart compression level? Please try with it if you use Lossless
• TinyPNG reduced image weight for less than 30kB, so it’s not significant gain
• Does the same happen for a lot of images in your Media Library? If so, is there a chance to send me a link to some of these so we could check?

Best Regards,
Marko