I am sorry you can't get it installed. I am not quite sure what the problem is all I can do is reassure you that thousands of people have managed to install it.

It would be useful if you could give me any system messages that occur against each point of the manual installation instructions.

There are two files Excel needs to have installed separately 1)XLC.dll (this is the toolbar component) and 2)XLC.xll (this contains special XLC functions).

PART 1 - Manually Install XLC.dll
=================================
Follow these instructions to register manually:
1) goto start button and select 'run'
2) type in 'cmd' this will get up a command prompt window.
3) Navigate to the xlc install directory (use 'cd' commands)
4) check using 'dir' that two files are present XLC.dll and XLC.xll
5) Register XLC.dll by typing 'regsvr32 XLC.dll' into the command prompt window. - you should get a message saying you have succeeded in registering.
6) Hopefully you can see the toolbar when you start Excel.

PART 2 - Manually Install XLC.xll
=================================
7) In Excel go to Tools>Add-Ins... This displays the Add-ins form.
8) From the add-ins form select the browse button and navigate to your XLC installation directory (normally this is C:\Program Files\XLC unless you installed it elsewhere). Select the xlc.xll and press 'OK'. This has manually installed xlc.xll
9) Close Excel and restart it again.
10) If all went well when you enter "=ovd(1)/und(2)" it will evaluate it as 0.5 and not give any "#NAME" error messages.

XLC is installed and working.

I am having the same problem, so cjscjs is not the only one.

I installed XLC.dll manually as you said in your instructions. When I open Excel, I get the error

Run-time error '1004':
Add method of AddIns class failed.

I do see the XLC toolbar at this stage but it doesn't work. Whenever I click on any of the buttons it asks me insert a hyperlink.

I then tried to install XLC.xll manually. At stage 3, I get the error message

'C:\Program Files\XLC\XLC.xll' is not a valid add-in.

If I close Excel and open it again, I still get Run-time error 1004.

Clearly this is a problem. It is strange because I have XLC working in Excel 2003 on XP with no problems. The thing that worries me most is when you get the message 'C:\Program Files\XLC\XLC.xll' is not a valid add-in. This could also give the "Run-time error '1004': Add method of AddIns class failed." associated with installation of XLC.dll. I have exhausted all the routes of enquiry and I fear that I might not find a solution for you.

I'll ask an old college friend and programming guru if he has any ideas. I'll get back to you later.

Let's do a quick check to see if it is a problem associated with XLC.xll.

Uninstall XLC and check that when Excel starts up that there are no error. OK

Now Do not install XLC.dll but go straight to PART 2 of the manual installation below. I am particularly interested in what happens at point 8.

PART 2 - Manually Install XLC.xll
=================================
7) In Excel go to Tools>Add-Ins... This displays the Add-ins form.
8) From the add-ins form select the browse button and navigate to your XLC installation directory (normally this is C:\Program Files\XLC unless you installed it elsewhere). Select the xlc.xll and press 'OK'. This has manually installed xlc.xll
9) Close Excel and restart it again.
10) If all went well when you enter "=ovd(1)/und(2)" it will evaluate it as 0.5 and not give any "#NAME" error messages.

I have tried what you suggested, but Excel still says that xlc.xll is not a valid add-in.

I have tried installing XLC on my home machine, which has XP Home Edition and Office 2003, and had no problems. I have also successfully installed it on another XP machine with Office 2000. So it appears to be a problem with the setup of my works machine somehow.

It begining to smell like an administrator rights issue to me. can your systems administrator log in and install it? Anyway at least you have it working on two other machines. Thank for your help with this but I am tempted to hang my boots up on this issue.