Hi all.
I'm posting this just in case somebody has come across this problem before.
A simple-looking case but I don't see what causes it.

I run a java-based web server that puts a database's data on a form and allows modification of the fields, some by direct entry and some by selecting from a dropdown list.
The form consists of a couple of frames and coded with Javascript (I didn't write it but I can see the code by browsing the page's source).

Problem: When I access the form from my laptop and hilight an option from a drop-down list (it gets highlighted as the mouse pointer moves over the list), I cannot select it. The clicks don't have any effect.

It should be some Javascript option in IE that causes this but which one?

Another computer on my intranet has no problem accessing that form.
Same OS (XP SP2), same security patches, same Java VM, same firewall, same security patches for IE, the exact same IE options. This computer is even more loaded and has a lot more of services running.

In the laptop, I removed all the IE plugins, disabled the firewall, made all Javascript options options enabled, low security, reregistered all the suggested DLLs as per MS instructions, and nothing. Same problem.

I thought it might even be the graphics driver (NVidia - the same version on both computers but different flavors of the chip) but Opera, on the laptop, works fine with that form so the problem should be something specific to IE.

I doubt it can be remote-fixed by anybody, unless you've come across this before, so the question is a bit more general.

How do you trace Javascript behavior on a case like this? Is there any tool that allows that? Alternatively, is there anything that can verify the correct setup of Javascript on a computer (other than reinstalling XP on top of itself)?
MS's Sfc didn't find anything and QfeCheck didn't identify any problems with the service patches.

Thanks in advance for any suggestions.

Reset all the internet options back to default.

I know its generic but, you need to have some base to start at.

When Opera works and IE doesnt then it can only be IE or Java.

What version of Java is Opera using ?

Woodmann

Thanks.
I'm running with everything in Default mode now and Low security. No difference in IE behavior.
Opera (7.60.7141) is installed without its own Java engine.
It shows as active the plugins installed by Sun's JRE 1.4.2_06.
Both computers use the same JRE but on the laptop I have it disabled now since I'm eliminating variables.
It didn't work when the JRE plugin was active anyway.
Funny thing too, this JRE is not an officially supported version by the application I'm running but it works fine on the desktop computer.
Eliminated the graphics driver too.
I tried in Safe mode and the problem remains.

Try an older version like 1.4.2_03

Woodmann

Can't be that, I'm afraid.
The working machine has 1.4.2_06 and works.
On the non-working machine, even removing the Sun JRE doesn't help.
It must be something specific to IE's Javascript that causes that. I'm still looking for some DLL that might have been overriden, but no luck yet.

I had a somewhat similar problem sometime ago. I could not select rows with a mouse click. The fact that you can do it in another computer with similar OS settings suggest to me that the problem is below OS Browser and JAVA: The mouse/touchpad driver may not be generating the expected harware event that the OS/JAVA software is expecting.

Suggestions:

Connect an extra mouse to the laptop: try a serial, a OS/2 and a USB and see if the problems solve. Also try to deactivate the intrinsic laptop mouse/touchpad device

Consider updating or, pain of pains, tracing the mouse driver event generation software in the computer that works and in the computer that does not. That is what I ended up doing. Good luck

Thanks.
I hope I don't have to go that route to resolve it. They'll have a new version out before I get halfway through
I'm already using an external mouse.
Nevertheless I disabled it, then I disabled the touchpad instead. Still the same. It's got to be some DLL. I have a bunch of Java development tools installed that might have overriden something.
The question is, what? How to identify all DLLs that MS Javascript uses? Is there a list of them somewhere?
It looks like I won't avoid the reinstall of XP on top of itself.

If you can spare a laptop hardrive or have an extra loaner laptop available, try starting with a fresh system, then see if the click mistake is present in a clean install. Then stepwise reconstruct your laptop system while using an install log utility. eventually, one of your tools installation will fuck up the click function, so you can narrow down the util/dll that has the problem.

Sounds involved , but it may take a few hours only. It all depends on how bad you want to squash this bug.

Thanks naides.
Your procedure is clean and would find the problem eventually but it isn't anything I want to have to try .
I can't get the extra hardware and this laptop has too many development tools on it. It would take me weeks to reinstall them. The missing functionality of this application doesn't bother me much since I can have it through other machines. But it annoys me that I can't figure out the "why"s of it.
I'll keep looking for this elusive problem. I'll post here if I ever resolve it.
Thank you all for the suggestions.