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Your LimeSurvey version: 5.3.6
Own server or LimeSurvey hosting: LimeSurvey Cloud
Survey theme/template: Fruity theme (?)
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Help I am a stressed out graduate student. 
I have two surveys that I am trying to send out to the same group of people. For the first survey, I followed all the instructions in the manual (Opened the survey, dowloaded the participant table, populated the first name, last name, email and attributes, uploaded the CSV file, applied toked to each participants, sent the email invitation). I put myself on this email list and received the email invitation without a problem. 

When I tried to do the exact same thing for my second survey, it says the emails were sent but I did not receive the email invitation. The surveys have different questions, and different email invitation scripts but everything else is the same. Am I only able to send out one survey within a certain period of time? I cannot figure out what is wrong with the second survey. 

Edmaneli_322571 wrote:

When I tried to do the exact same thing for my second survey, it says the emails were sent but I did not receive the email invitation. The surveys have different questions, and different email invitation scripts but everything else is the same.
 

Via what service did you sent the emails?
The Email method is LimeSurveyCloud or SMTP.
In SMTP you can use any E-Mailaccount you have created and use the Mailserver of that E-Mailaccount ( That is the solution with most control over the email flow).
Or the Email method is LimeSurvey Cloud, which sents the E-Mails via a server managed by LimeSurvey.

The situation you describe can happen with any method. Sometimes E-mail provider block E-mails with survey invitations.They are seen a  form of SPAM. If many people use a mailserver the mailserver could be blocked by E-Mailservers cause of a lot of unwanted E-mails are sent.
Where is you E-Mail account hosted?