issue connecting some users to on-prem exchange server

Question

hello all

we experience some issue with some user when we tries to connect account to exchange on prem server.

we build a new exchange server on exchange 2019.

for some user no impact but for few we get a message saying : cannot start Microsoft outlook. cannot open the outlook windows. the set of folders cannot be opened. the information store could not be opened.

I tries to redo the profile same issue we get the error when we start outlook we get a security warning about certificate with 3 options

yes / no / of view certificate

if we press yes we get the message if we press no outlook close

we never have to install the certificate before and even if we do it's not working

i was able to configure my self on one machine but on another machine it wont work i get the popup

we notice that when a user came back after the week end she get the security warning and then it stop working all other users that are already configured it work but new user it wont OWA is working without issue

we tries office 2016 and 2021 same issue

really need to find a solution

Thanks

Answer 1

Hi @POJ

Glad to see that your issue had already been resolved and thanks for sharing the solution so that others experiencing the same thing can easily reference this! Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution in case you'd like to "Accept" the answer.

 

 

 

[issue connecting some users to on-prem exchange server]

 

Issue Symptom:

for some user no impact but for few we get a message saying : cannot start Microsoft outlook. cannot open the outlook windows. the set of folders cannot be opened. the information store could not be opened.

 

Solution:

we found out that the use didn't have the reg key :

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Exchange]

"MapiHttpDisabled"=dword:00000001

Best regards,

Jarvis

Answer 2

Hi @POJ ,

Thanks for posting in our Q&A forum.

According to your description, the first thing you should do is to check whether the name of the certificate and the mail server is the same or not. For establishing a connection between the mail server and email client, it is necessary to have the name of the mail server on the security certificate.

Follow the steps to verify the name on the certificate.

• As the Outlook security certificate error appears, click on View Certificate.
• Select the Issued to Name option and check whether the name on the certificate is the same as the mail server.
• If both are not the same, change it and then restart the application.

Hope it can help and if there is any update, please feel free to let us know.

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Answer 3

Hello

everything is the same

for some user it ok but if i try to connect outlook to a new machine i get certificate warning i have the choice of yes no or view certificate

when i tries for me it working on one pc and not on the other one ...

is it possible that a dns entry (autodiscover) cause that ?

Thanks

Answer 4

hello

we found out that the use didn't have the reg key :

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Exchange]

"MapiHttpDisabled"=dword:00000001

present after inserting it seem it start to work .