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Your LimeSurvey version: 3.22.17
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We are running LS 3.22.17 and are unable to upgrade to LS 5. Is 3.22.17 compatible with PHP 8? Our current version of PHP is 7.4.

Thank you for any info. I saw another thread that said LS 5 and up was compatible w/ PHP 8, but not version 3.x.
 

I recommend to stay on PHP 7.X with LS3. LS3 will run with PHP 8.0.X, but issues may occur and there is no testing of LS3 under PHP 8. You won't find an official recommendation to run LS 3 under PHP 8. Reported bugs may be fixed if reported, but investing that time in LS5 seems to be a better investment.

You can install LS3 on PHP8 but it is officially not supported.
LS5 supports currrently 8.0, but not 8.1, yet.

Hi, as PHP 7.4 is reaching its end of life November, 28th, I would like to ask whether the LTS 3.x will or does already officially support PHP 8.

In the release notes I find this:

> Changes from 3.26.3 (build 210511) to 3.26.4 (build 210517) May 17, 2021
[...]
> -Fixed issue #17236: PHP 8 not supported (Carsten Schmitz)

Does this mean that from 3.26.4 up, PHP 8 is supported?

Looking closer into the topic, as the date for end of support for 7.x approaches, I find that unfortunately there is no reliable info at bugs.limesurvey.org/view.php?id=17236 ; the relevant links mentioned there do not work, and so we cannot be sure whether this has been resolved, and PHP 8 can now be used with the LTS or not.

Can anybody update us on this topic?

I would rather make a comment in the bug reports than here. The developers don't follow the forum very closely and people here in the forum are mainly users helping users. So I think chances are higher that you get feedback in the bug tracker.