Quicktime movie will not play - and crashes IE

[Londoner]

Hi, I recently reformatted my HD, and did a clean reinstall of Windows XP. The only real new addition to my system is of Norton Security 2002 (firewall, antivirus, privacy control, etc). I regularly use a very useful software tutorial site (lynda.com) which uses streaming Quicktime movies to teach software to subscribers through the site. I have never experienced any difficulties with this site or the movies playing until now.

Most of the movies run fine, but every now and then one of them halts at a certain point and I get the 'Internet Explorer has encountered a problem and needs to close' message. The error report reads:
Error signature - AppName: iexplore.exe Appver: 6.0.2800.1106 ModName: quicktimeessentials.qtx ModVer: 6.5.0.48 offset: 000179bc

The curious thing is that this only happens on certain movies, and when it does it happens in exactly the same place without fail. Some other movies only download, say, 3/4 of the movie and will not download any further. I have never had any previous problems with this site or the movies so I must assume something in my system and/or setup has changed.

I have tried running it in MSN Explorer but the issue repeats the same. I have tried deleting temp files and reinstalling Quicktime, I have checked that my graphics card drivers are up to date, but so far nothing has caused this issue to stop occurring.


My spec:
Windows XP Home Edition (5.1, build 2600) and Service pack 1, running Norton Security 2002 (Firewall, Antivirus, privacy control, etc).

BIOS: Award Modular BIOS v6.00PG
Processor: AMD Athlon(tm) XP 1800+, MMX, 3DNow, ~1.5GHz
Memory: 512MB RAM (2x sticks of 256mb ddr)
Motherboard: Gigabyte
DirectX Version: DirectX 9.0b
Main HD: ExelStor 40gb
Slave: Seagate Barracuda 120gb
Graphics card: NVidia 440
Sound card: Audigy

[Londoner]

ok, it's beginning to look like this is down to Norton Security interference..

[glc]

I wouldn't doubt it - 2002 is an old version, and NIS is a royal pain in the butt on a GOOD day.