New version 2.5.5 causes Internal Server error 500

same problem here.

Yep, same problem here as well. Single sites updated fine but my multi-site crashed with the Internal Server Error 500. Reverted back a version until it gets addressed.

Yes, I got the same problem and it caused me hours of work to isolate this. 100% causing the issue. I restored my site to a backup I took two hours before the Internal Server error 500 started. I had installed a couple of new plugins and upgraded EWWW Image Optimizer after that backup was taken. After restoring, I retraced my steps, performing one change at a time and backing up prior to each change. The very last thing I did was upgrade the EWWW plugin, and as soon as I did, the error returned.

I was able to reproduce the error twice in a row.

FYI – this is happening with a Multisite Installation. Haven’t tried any single site installations yet.

same here

Appears to be a problem (as reported in 4 other threads) with the debugging options. Can anyone disable debugging (with 2.5.4 installed) and then retry the upgrade?

Potential fix, soon as I have confirmation from someone (besides myself) that it works, I’ll release it officially: https://downloads.www.ads-software.com/plugin/ewww-image-optimizer.zip

Just rolled out 2.5.6 with the fix!

Yeah, thanks, but sorry I can’t afford for a plugin to take down an entire website – actually a whole network of websites. I went back to WP Smush Pro. I only switched to yours because it claimed to work with a CDN better than Smush.