SharePoint and Exchange Calendar together


Hi SharePoint folks, one of the cool things in SharePoint 2010 is the ability to show the Exchange Calendar on a SharePoint site, side by side. This is called as Calendar Overlay

This blog will give you step by step on how to configure this.

Step 1 (PRE- REQ)

1. I have a SharePoint Site http://fabrikam which looks like this


2. I also have a calendar “MySharePointCalender” , I have few events there too.


3. I have my Exchange Calendar, here it is in outlook, I have couple of meeting/events there too


4. Now What we want is to see this exchange calendar in my SharePoint site’s

Step 2 (The actual process)

1. Open the SharePoint calendar >calendar Overlay>New Calender> Fill in the :

-Name: Give a name to this calendar

-Type: Select Exchange

-Outlook Web Access URL: the OWA url of your organization.

-Exchange Web Service URL: this is usually like this

NOTE: If your owa url is ,

Then the Exchange web Service url would be

(in simple words from owa url , remove the trailing “owa” and add “ews/exchange.asmx” )

That is all !!

And check Always Show.






Step 3 (The awaiting Error and the fix)

Most of us who have tried this must have got the error

“ Could not establish trust relationship for the SSL/TLS secure channel with authority ”


Here is the fix

1. Get the CA Root Certificate

(Just a note, there are many ways to get the certificate, I’m taking the one that is less prone to error)

a. Go to the Server where you have the Certificate Authority installed. Open IIS and select the Server Certificates component.



Double click on Server Certificates

Locate the Root Certificate of the CA from the list, here is the one what I have.


(To double check if this it the Root certificate, open the certificate and see the certification path, It should have just one entry (root), that is the name of the Certification Authority, in your domain.). Below the image or my root certificate


b. Now that we have located the certificate, Open it go to Details tab and Click Copy to File

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And now we have the Certificate exported to a file


Now take this certificate to the SharePoint Server, and follow the below steps

a. Open the Central administration > Security> Manage Trust


b. Click on New, Provide a Name (I use RootCA), and navigate to the RootCA.cer file you exported in the previous step. And Click OK


That is All (For Now J,but some “good to have” stuff on this is below)

Ok Now refresh the same calendar and see that you Exchange calendar event (the logged in users)


Step 4 (Enhance the default behavior)

Now we see the exchange calendar, BUT, We DO NOT see the actual details of the event, default we see it’s just busy, But it would be good if we have the details displayed here too. Ok let get the details, follow the steps below

1. Open Outlook> File > Options>


2. Go to Calendar Section > click Free/Busy Options


3. Select any one of the options below, I have selected Full details. Click Apply and Ok and exit out of the outlook, Now refresh the SharePoint calendar and see the difference.



I hope this would be good. Comments are welcome.

Additional reading:

The calendar Overlay is per user, meaning it would only be seen for the user who has set it.