A company I work for, which shall remain nameless, sadly still uses IBM's Lotus Notes. In fact they recently upgraded to version 7. After being a notes user for a few years now and working with hundreds of different software applications over the years I am convinced that Lotus Notes is in fact the WORST piece of software in existence. If you have never suffered through the difficulties of attempting to use it count yourself lucky.
First of all the user interface is extremely archaic and gives you that late 1980's feel. It looks like something that should be running on the Apple IIe right alongside the Oregon Trail. If that isn't bad enough the different user options to change configurations and settings are located in about 6 different places and nearly impossible to find in some cases. The overall layout of the program does not come anywhere near the standards of most modern Windows programs.
Second it is an absolute resource hog. Even on decent hardware it uses an incredible amount of memory and system resources while just running in the background. More than any common email client (Thunderbird, Outlook, etc...) that I have ever used.Third it lacks many features common to modern email clients unless you wish to program agents. These agents are over-complicated and difficult at best to understand. In almost every other client I have worked with these features are set-up via check boxes and simple input fields. It does however have a vacation auto responder. Unfortunately after the system receives a new message it could take hours or even days before your vacation auto response is actually sent back to the message sender.
Lastly and perhaps the most frustrating characteristic of Lotus is the fact that it is incredibly unstable and prone to crashing. When it crahses it almost always requires a system restart before it will run again. On top of all that the Lotus folks have written some of the most difficult to understand and nonsensical error messages that I have ever seen. What exactly does; "Type Mismatch" tell the user? Or another one of my personal favorites; "An error occurred while processing a request on an object"
If you are an IT administrator considering implementing Lotus Notes in your organization: DON'T. It lacks many common and useful features, it is insanely over-priced, and it is riddled with problems. If you are using it already switch to something else... fast. You'll be glad you did. And if you are poor user stuck with notes and you hate it... at least your not alone. Check out THIS SITE.