TL;DR: if you ever turn on "prevent multiple submissions" and are sending your survey via email, then you'll want to enable the "Security scan monitor" option.
I ran into a very similar problem before. I'm not sure if this is what's happening to you, but, here's what happened to me.
People were getting the survey to their email, and their email security system was automatically testing out the survey link to check for security issues. This triggered the "countdown" in Qualtrics - respondents then had 1 week to complete the survey or else the system would record that as a partial response. Life happens, and many people waited more than 1 week to take our survey... so they were locked out. Since "prevent multiple submissions" was turned on in our survey, they were not able to go back into the survey later and complete it for real.
A few things for you to check:

• In Survey Options - Responses, what are your settings for "Incomplete survey responses"? The default is to record after 1 week.


• About how long ago did you first distribute the survey? Is this more/less than the time you have set to record incomplete survey responses?


• In Survey Options - Security, what are your settings for "Prevent multiple submissions"? Mine was set to prevent ballot box stuffing (turned on), so people could only submit the survey once.


• In Survey Options - Security, what are your settings for for "Security scan monitor"? I believe the default is OFF (which is what mine was set to when I was having issues). You'll want to turn this ON.



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Hi Liz , thanks for your response and it is very helpful, but in our case the Incomplete survey responses was 1 month so and we distributed the survey on the 15th 7AM UK time and people who went in to take it on the 15th around 9 AM for the first time and received this error, so clearly the incomplete survey responses does not seem to be an issue here , we also have the prevent multiple submission as ON for our survey but here the respondent was not even able to open the survey questions even for once, they got the error the moment they clicked on this link, however the last setting around the security monitor was OFF by default so i think this could be one of the reasons since we did not have the Qualtrics IP addresses whitelisted, can you also confirm if in your case did you get the Qualtrics addresses whitelisted before distributing the survey?

HI Manjista We've had something similar when a 'helpful' person shared their personal link with others trying to encourage completion. One of them went in and completed the survey, and then none of the others could access that link. Not sure if this might have happened with your survey? Good luck, Val

Good afternoon from a cloudy Sweden!
Manjista , is the email using an Inline question in the design? Are you seeing responses come in with 0% progress but are still recorded as submitted (and not as "In progress")?
We have just experienced security programs fill in the NPs score of the survey and submit the survey as "Completed" although 0% process was recorded (it's a 1-page survey) and it also bypassed both the reCAPTCHA and a mandatory question in the survey. Very strange.
So depending on the data you've received back, perhaps we're having the same issue

All the best
-Mattias