Pop up message that says ‘cannot verify server

For the last few days I have been getting a pop up message on my iPhone that says:

’Cannot verify server identity- the identity of pu4.biz cannot be verified’


My phone model is iPhone XR running on IOS 18.5


Why am I getting this message and how do I remove it?

iPhone XR, iOS 18

Posted on Sep 9, 2025 5:24 AM

Reply
1 reply

Sep 9, 2025 5:35 AM in response to Roxy_65

Your may have a subscribed Calendar or a CalDAV or a CardDAV/LDAP account for Contacts or Calendars.



What happens when you click the "Details" on the error popup message (See the Pic below)



The best would be to Delete and Add the email account that is creating the issue.


You may also try changing SSL settings


Settings > Password & Accounts > [Select the Mail account} > [Tape on Account with the email ID} > Advanced > SSL Settings > [Disable]

Click <Account (in Blue)

Click on DONE (in Blue) when exiting in the previous screen




Probably you may have accepted an offer or subscribed for a spam Calendar accidentally. Watch the GIF below to know how to unsubscribe from these calendars. Look for an unknown Calendar on the device under subscribed calendars.




The pic below is self-explanatory if you have subscribed to a calendar.


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Pop up message that says ‘cannot verify server

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