Microsoft Exchange and Remote Desktop Services Specialists


Microsoft Exchange Server and
Blackberry Enterprise Server news, views and fixes.

Exchange 2010 Database Sizes

The blog is getting lots of search engine hits for Exchange 2010 databases, probably because I wrote about the database size on the older versions in the past.

For older versions of Exchange see the posting here:

For Exchange 2010, things are much the same.
On standard edition, the initial soft limit is 50gb, which can be increased as required. Enterprise edition has no limit configured.

To change the soft limit, you need to make a registry change and then restart the information store. The registry change is outlined in this article:

Note that the change is case sensitive.
If copying from the article, watch that it doesn't include an extra space at the end.

If you have the registry key set correctly, after restarting the information store, the following entry will be logged:

Log Name:      Application
Source:        MSExchangeIS Mailbox Store
Date:          29/07/2010 22:07:52
Event ID:      1216
Task Category: Storage Limits
Level:         Information
Keywords:      Classic
User:          N/A
Computer:      exch.domain.local
The Exchange store Mailbox Database 1 is limited to 75 GB. The current physical size of this database (the .edb file) is <1 GB. If the physical size of this database minus its logical free space exceeds the limit of 75 GB, the database will be dismounted on a regular basis.

As with Exchange database since 2003 SP2, when the limit is reached, the database is dismounted. It can be remounted again immediately. However it will be dismounted at the next time the limit is checked, unless the registry has been changed and the information store service restarted.
The white space in the database continues to be taken in to account when the size is calculated - referred to as logical free space in this event log entry.

Outlook 2007 Certificate Prompts with Exchange 2003

A common complaint in forums for some time has been SSL certificate prompts from Outlook 2007, when running Exchange 2003.
The error is usually along the lines of

"The name on the security certificate is invalid or doesn't match the name of the site."

Often the first response will be connected to RPC over HTTPS, as this is the only part of Exchange 2003 that can use SSL certificates for Outlook connectivity.

However the real cause of this is because of the changes made to Outlook 2007 to accommodate the changes to Exchange 2007 and its move to web services. Web services are used to reduce the dependency on Public Folders.

The specific cause of this is a process known as autodiscover. Anyone who has managed Exchange 2007 will be very familiar with Autodiscover, as it can be a key pain point.

Outlook 2007 will attempt to connect to - where is the part of your email address after the @ sign. It will also attempt to connect to a number  of other URLs if that one fails.
If your domain does not have an entry for autodiscover, but does have a wildcard entry in its DNS (which is common) then you may get this issue.

Therefore from a client where you have the problem, attempt to ping

Where is your email domain, then repeat with your internal Windows domain.

If it resolves, pinging either, or similar, even if it fails, then you may well be on to the cause. The final test is to bring up a web browser and type in and see what happens.
It is likely that you will get the same SSL certificate prompt that Outlook receives and then it will load another web site completely.

The reason for this is quite simple.
Web hosts will often share the IP address of their server with a number of web sites, could be 100s. However to use SSL, a web site must have a dedicated IP address. Therefore a single web site with that IP address will have SSL support.
By using a wildcard in your DNS (so resolves) means that all hosts will resolve to the same IP address.
As SSL cannot share an IP address, and does not see the host name being used, it will connect, and generate the SSL certificate mismatch.

How to resolve? Either remove the wildcard entry on the external DNS or have an entry for put in to your domain with a dummy IP address - for example. This will cause the host name to resolve, but fail to connect. See the single host replacement method on this page for instructions on how to do it:

However if you ever deploy Exchange 2007 or higher then remember to remove it!

Short URL for

One of the most useful online tools to come out of Microsoft for the Exchange product is their testexchangeconnectivity site - or to give it's correct name - the Microsoft Exchange Remote Connectivity Analyzer (ExRCA). However the URL is a mouthful, and if you are typing it as often as I do, it is easy to make mistakes.

Therefore I have setup a short URL for it using our Exchange community site  - you can get to it via

I was going to use (which also works) but I thought et would be easier to remember.

New Site Launch -

Today we have launched a new web site - This is a development of an internal site that was built in a hurry after the Paddington exchange flood in March 2010 and is our first all new site launch since was created in December 2009 - all others have been existing content spun out to their own sites.

At the moment it is simply a list of links to the status pages for most of the biggest ISPs in the UK, along with BT, and some other internet based services. Not all ISPs have status pages, so where they cannot be found they are not included.

If you are supporting clients on multiple ISPs then this page could be useful, as it is a single location for the list, which we intend to keep up to date.

The site may be developed over time, but we believe it will be a useful resource in its current format.

Related Links home page:
ISP Status Pages:
Phone Services Status pages:
Other Internet Services Status pages:

Blog - All Change

Its all change here on and I have an apology to make to visitors.

First the change. If you aren't reading this on the RSS feed, then you will have noticed things look a little bit different. This is because I have changed the blog engine that I am using.

Since I started blogging in 2007 I have used Community Server, nursed back to life after two server failures, plus version upgrades. However with the change of my underlying OS to Windows 2008 R2, I decided it was time to switch to something a little more basic. I only used the blogging functionality of Community Server, nothing else. Plus I wanted to drop the SQL database dependency.

Therefore I have switched to The change was relatively painless, I was running with it on a private URL in less than 30 minutes. What took the time was putting redirect files in to place so that URLs were redirected to the new format. That is now complete (I hope).

You might find that the theme changes, I am still looking for one that I am 100% happy with, and may end up creating my own, or getting one created for me to match the other sites that I have through Sembee Ltd. I haven't quite decided. The content will stay the same.
The HTML code is a bit odd in places, which I will correct as I find the postings, but that is a display issue, nothing more.

Comments are still turned off, because I have seen then turn in to support forums before, and blogs are a really bad way for that kind of thing - use a forum instead. 

Now for the apology.

If you sent a message through the Contact option in the previous Community Server based blog format, then I didn't receive it. I had thought I had disabled all of the options for contact via the blog itself, preferring to receive direct email messages. However when I started to pull the original installation of Community Server apart, I found 70 pages of contact attempts in a location I had never looked at before - called "Feedback". Most of it was spam, and was deleted, but there were still seven pages of legitimate messages, dating back to 2008. I hadn't seen of them.

Big oops.

I am not going to reply to the lost messages now, as they will be very old and no longer relevant. However if you sent me a message via the blog and did not get a reply, it wasn't intentional. They simply went in to a location I didn't know was there.