I have made a few surveys successfully but now with the new one this message keeps coming up when I try out the survey:

Did not save
An unexpected error has occurred and your responses cannot be saved.
Your responses have not been lost and have been emailed to the survey administrator and will be entered into our database at a later point.

I tried with and without tokens. Even with the 'execute this survey' option this message comes up.
I am using Limesurvey 2.06+

I would be very grateful for any help!

Please post the exact version/build of LimeSurvey. 2.06+ isn't specific enough.
What kind of hosting is used for running LimeSurvey?

Next steps:
1. Activate the survey and then test the survey url via the anonymous mode of your browser (or use a different browser).
2. Copy the survey and repeat the test above with the copy of your survey.
3. Create a new simple survey and repeat the test.
Report back, if you receive this kind of error in all three tests.

Thank you!
It's Version 2.06+ Build 151018. Is that enough information? We're using the online programme.

I went through your steps. Another browser does not work and a copy of the survey does not work either, but a new simple survey works fine. So the problem is with the survey I guess?

Noortje888 wrote: We're using the online programme.

You mean Limeservice.com? They have a support via email. I would ask them about that issue.

Noortje888 wrote: So the problem is with the survey I guess?

I cannot tell you for sure.
I would now use a copy of the "buggy" survey and try to undo the last things that were done in that survey.
If that is unclear I would remove questions and check, if the error is still existing. Perhaps there is only one question buggy.

Next step:
Make a few copies.
In the first copy add a new question and remove everything else.
If the issue still exists, its not in the questions.
You then better create a new survey and begin to import questions from the old survey.
If the issue is gone, you might just remove question by question from a copy and test if the problem is gone.

It still can be issue in LimeSurvey, which only occurs in certain circumstances.

Thank you for your help, I will try and go through your steps!