It is possible that this is due to viruses in your system, so check ur full system with good anti-virus. I suggest, for MWAV (not escan & it is completely free) for emergency scan.
One more thing might be, occurred when another program has registered itself as the default application for browsing the web. If this program is not well written, or it has been uninstalled, Outlook Express cannot launch a browser window when you click on a link within an email. To overcome this issue, must re-register Internet Explorer as the default browser. To do this:
Open IE and click Tools >Internet Options menu > Programs tab
Look for a checkbox where "Internet Explorer should check to see whether it is the default browser", If this checkbox is not ticked, checked it, now click OK. Close IE and again open IE
and close Outlook Express and re open Outlook Express.....
For complete info : http://support.microsoft.com/kb/929867
Also. Try a fresh install of outlook express. That usually works
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"Also. Try a fresh install of outlook....", this is not a good idea. A computer has problem, that does not mean to format it first, without taking other considerations.
To fix this problem, follow these steps:
Click Start, click Run, type the following command in the Run dialog box, and then click OK:
regsvr32 urlmon.dll
Repeat step 1 for each of the following commands:
regsvr32 mshtml.dll
regsvr32 shdocvw.dll
regsvr32 browseui.dll
regsvr32 msjava.dll
Just giving my 2 cents worth here
but I work in tech support and sometimes when users install another browser it set itself as the default browser and this stops user from clickingon hyperlinks in mail
what I did to resolve this is simple
reset IE to default
close outlook/express and IE and reopen
If this does not work this is what I did and it has worked every time
open a notepad
type in the following
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINESOFTWAREClasseshtmlfileshellopencommand]
@=”"C:\Program Files\Internet Explorer\IEXPLORE.EXE” -nohome”
save it as a .reg file and execute it
close IE, Outlook/Express and restart them and it should work (it does for me at least)
HTH
Shane