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LimeSurvey version: LimeSurvey Community Edition   Version 6.15.2+250628 
Own server or LimeSurvey Cloud: Own server (shared provider VentraIP)
Survey theme/template: fruity
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I have been using LimeSurvey without trouble for the last year and a half on a shared hosting platform. For some reason, I am now unable to add participants or send invites. I get a blue spinner when I click on "new participant" or "send email invitation". 

I used ComfortUpdate just now and the issue persists with the updated version.

I copied the previously working survey to a new survey and I am able to add batch dummy participants but I can't make a new participant in the new survey - blue spinner.

Any troubleshooting ideas or tips?

I've been using LimeSurvey for almost 10 years and haven't had this particular problem.

 

Update on this one - I tried installing a new copy of LimeSurvey on a new subdomain. It's all set up. I created a new test survey and it still can't add participants.

I've tried
1. two different browsers (safari and chrome)
2. Incognito/private modes
3. clearing browsing data

This feels like there is some problem on my end but I can't figure it out. Any suggestions?

This sounds weird. Usually shared hostings have their limitations, but adding a single user shouldn't be a problem, even for a shared hosting environment. If it would be a huge CSV file with a lot of participants I could see an issue with a shared hoster.

I imported your LSS file and what I noticed is that your questions seem to be in the wrong order.

Just as a heads up.

I added a new participant through the participant section by clicking on "+ Add..." - "Add participant". I had no problem creating a new participant on LS 6.15.2+250628.

No "blue spinner". What makes me wonder is this "blue". I am not aware of any blue elements in the admin theme.

Could you show a screenshot of this blue spinner? I don't recognize this.

Thanks for the response. I just got a response from the hosting provider.

"When using the credentials provided and attempting to create a new participant, we can see the following error within the Dev Console

Failed to load resource: the server responded with a status of 503 ()
"

They are asking if there are more logs that might shed more light on this. Any suggestions?

I think the spinner is an OS thing. On iOS I get a grey screen. On windows I get a blue spinner with a hole in the middle. Regardless, it seems it's a 503 holding things up.

Interestingly, I just got a notification that the database had been updated from 623 to 630 and I can open the add participant page now. This happened after I changed the logging preferences in the config.php file to

'config'=>array(
'debug'=>2,
'debugsql'=>1,

Not sure if these things are related or not.

But, when I change debug and debugsql back to zero (0), I can't create a new participant. So strange.