I ran into this issue recently where upgrading a SSL Cert on a Outlook Web Access (OWA) web server can cause a "Internent Explorer cannot display the Webpage" error after successfully upgrading the certificate.  After checking the usual stuff...<!--more-->
<ul>
	<li>Default Website and Exchange sub folder in IIS is "SSL Only/Requires Encryption"</li>
	<li>The directory security settings are set to allow anonymous access.</li>
	<li>We are not using Forms Authentication in Exchange Admin.</li>
	<li>The SSL cert shows up and appears to be applied correctly.</li>
</ul>
After all of these were tested I turned off SSL and made sure I could browse to the site using http: instead of https:.  All looked good.  Other than when switching back to Https: we would still get the error above.  I found a solution in the MSFT knowledge base that can fix one cause of this issue.  The cause is that the SSL certificate is not associated with a private key or that private key needs to be "repaired".  This can happen for a few reasons. One, the base certificate was removed instead of upgraded.  Two, there was a corruption that caused the private key not to be associated.

To determine if this is your issue.
<ol>
	<li>Open IIS.</li>
	<li>Right Click your OWA site</li>
	<li>Select Properties</li>
	<li>Select the DirectorySecurity Tab</li>
	<li>View the certificate.</li>
	<li>If the certificate does not say it is associated with a private key then this is most likely your issue.</li>
</ol>
To remedy this follow these steps or this KB for more details... <a href="http://technet.microsoft.com/en-us/library/cc759048.aspx">http://technet.microsoft.com/en-us/library/cc759048.aspx</a> (Install certificate after deleting the peding certificate request).  This works for our situation as well.
<ol>
	<li>When viewing the certificate in IIS.  Go to the certificate details and copy down the Serial Number (omitting the spaces).</li>
	<li>Open up the Command Prompt.</li>
	<li>Type <em>certutil -repairstore my "serialnumberhereinsidequotes"</em></li>
	<li>Press Enter.</li>
	<li>View the cert in IIS again.  You should see that it is now associated with a private key.</li>
	<li>Browse to your https:// OWA site and you should be all set.</li>
</ol>
Good Luck!