XenForo upgrade check failed: Unexpected result, starting '<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title>

[lazy llama]

I'm assuming this is a temporary glitch at the XenForo end but I've seen a few other people reporting the same issue (though possibly misattributing it to the XF Bot Guard add-on) - https://xenforo.com/community/threads/xf-bot-guard.237990/post-1784823 and https://xenforo.com/community/threads/xf-bot-guard.237990/post-1784878

It appears that something is intercepting the customer boards request for the latest update info with a "Just a moment..." interim page?
Possibly Cloudflare?

Spoiler: Stack Trace

• GuzzleHttp\Exception\InvalidArgumentException: XenForo upgrade check failed: Unexpected result, starting '<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta data-fr-http-equiv="Content-Typ' // json_decode error: Syntax error
• src/vendor/guzzlehttp/guzzle/src/Utils.php:277
• Generated by: Unknown account
• Jun 11, 2026 at 6:59 AM

Stack trace​

#0 src/XF/Service/Upgrade/CheckerService.php(98): GuzzleHttp\Utils::jsonDecode('<!DOCTYPE html>...', true)
#1 src/XF/Job/UpgradeCheck.php(37): XF\Service\Upgrade\CheckerService->check()
#2 src/XF/Job/UpgradeCheck.php(12): XF\Job\UpgradeCheck->performUpgradeCheck()
#3 src/XF/Job/Manager.php(275): XF\Job\UpgradeCheck->run(8)
#4 src/XF/Job/Manager.php(205): XF\Job\Manager->runJobInternal(Array, 8)
#5 src/XF/Job/Manager.php(89): XF\Job\Manager->runJobEntry(Array, 8)
#6 job.php(46): XF\Job\Manager->runQueue(false, 8)
#7 {main}

Request state​

array(4) {
["url"] => string(15) "/forums/job.php"
["referrer"] => string(31) "https://myboardurl/"
["_GET"] => array(0) {
}
["_POST"] => array(0) {
}
}

 

[zeeb0t]

Just to follow up - as the author of Bot Guard, it is not the Bot Guard interstitial being seen. It has the Cloudflare signature on XenForo’s site. Also, non add-on users are reporting it also.

 

[Chris D]

I'm assuming this is a temporary glitch at the XenForo end but I've seen a few other people reporting the same issue (though possibly misattributing it to the XF Bot Guard add-on) - https://xenforo.com/community/threads/xf-bot-guard.237990/post-1784823 and https://xenforo.com/community/threads/xf-bot-guard.237990/post-1784878

It appears that something is intercepting the customer boards request for the latest update info with a "Just a moment..." interim page?
Possibly Cloudflare?

Spoiler: Stack Trace

• GuzzleHttp\Exception\InvalidArgumentException: XenForo upgrade check failed: Unexpected result, starting '<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta data-fr-http-equiv="Content-Typ' // json_decode error: Syntax error
• src/vendor/guzzlehttp/guzzle/src/Utils.php:277
• Generated by: Unknown account
• Jun 11, 2026 at 6:59 AM

Stack trace​

#0 src/XF/Service/Upgrade/CheckerService.php(98): GuzzleHttp\Utils::jsonDecode('<!DOCTYPE html>...', true)
#1 src/XF/Job/UpgradeCheck.php(37): XF\Service\Upgrade\CheckerService->check()
#2 src/XF/Job/UpgradeCheck.php(12): XF\Job\UpgradeCheck->performUpgradeCheck()
#3 src/XF/Job/Manager.php(275): XF\Job\UpgradeCheck->run(8)
#4 src/XF/Job/Manager.php(205): XF\Job\Manager->runJobInternal(Array, 8)
#5 src/XF/Job/Manager.php(89): XF\Job\Manager->runJobEntry(Array, 8)
#6 job.php(46): XF\Job\Manager->runQueue(false, 8)
#7 {main}

Request state​

array(4) {
["url"] => string(15) "/forums/job.php"
["referrer"] => string(31) "https://myboardurl/"
["_GET"] => array(0) {
}
["_POST"] => array(0) {
}
}

Yes there may have been a temporary issue with us receiving some API requests. and likely unrelated to the Bot Guard add-on you are running. Can you please go to Admin > Tools > Check for upgrades > Check now... and see if the issue is resolved?

 

[lazy llama]

Thanks, @Chris D - yes, retrying manually works (and I think others found the same).
I'm not (yet) running the XF Bot Guard so was pretty sure it wasn't that .
The other reports seem to be from yesterday and this morning, so that aligns with it being a temporary issue.

 

[Rhody]

Yea re-trying worked fine here, too, and it seems to be resolved. I was one who added XF Bot Guard and Cloudflare this week, to combat the bots (with success!), and had the issue overnight.

Thank you for letting us know.

 

[Suzanne O]

Had that as well and asked via a support ticket.
As what Chris D just explained it was on their end.
Checked the upgrade button again and it was resolved.
Thanks for resolving it XF staff.