i guess ur using a licensed and updated antivirus (i prefer avg/kaspersky)..!!
this is a common problem now days, probably itz caused by a virus/trojan..
download microsoft kb890830, install n run
also possibilities of:
u may not hv java runtime/adobe flash player/shockwave player installed..
the windows firewall is limiting the site..
may b ur antivirus is doing so..
some spyware/trojan horse also may play foul..
sometime it also depends upon the browser u r using..
it is black-listed or restricted by using 'content advisor' (in case of
internet explorer) in ur computer by some user or the above..
may b it is being filtered by the 'phishing filter'..
there may b possibilities that the site may contain 'active content'..
the Software part:..
a licensed and UPDATED antivirus installed (i prefer avg/kaspersky,
remember, without updation a full version antivirus is useless)..
2) download, install n run microsoft kb890830..http://www.microsoft.com/downloads/details.aspx?FamilyId=AD724AE0-E72D-4F54-9AB3-75B8EB148356&displaylang=en
3) download n run Startup Control Panel..http://download.cnet.com/Startup-Control-Panel/3000-2094_4-10039330.html
all the unnecessary startup items from here..(if u can't find what
to remove, post me/us in ur comment with all the items listed in each
n every tabs herein)..
4) remove all unnecessary software from add/remove programs..
5) download, install n run 'Advanced System Care Pro'..http://download.cnet.com/Advanced-SystemCare-Pro/3000-2086_4-10399324.html
6)disable the following:..
right click on my computer->properties->advanced->startup
n recovery->(uncheck on the) Automatically Restart;
right click on
my computer->properties->advanced->error reporting->disable
error reporting->(uncheck on the) 'but notify me when critical error
7) Increase the size of Virtual Memory, Initial: 1440; Maximum: 2880
if u r bot a professional, always better to seek advise from ur system admin/vendor....