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Help with duplicate signups (contacts)


Help with duplicate signups (contacts)

Just spent 30 minutes on the phone with CTCT - they suggested I reach out to the people here for help.  I have a CTCT account.  Potental contacts can either signup directly from our CTCT account signup or from a php page we created.  My issue is that every now and then when someone signs up - the signup gets duplicated.   How can I stop this from happening?



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Signup Date

Contact Email Address 

First Name 

Last Name 










Re: Help with duplicate signups (contacts)

Without knowing what your PHP script is doing, but guessing from the time stamps you shared, this could be caused by a known issue that we are not currently planning on fixing.  We are aware that if the same contact is attempted to be created at nearly the same time, it can cause a duplicate contact to be created.  This race condition is not normally seen by customers in production environments but it could be what you're seeing here. 


We can look into this further but would need you to share your PHP code with us. 


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Dave Berard
Senior Product Manager, Constant Contact
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