We have recently set up the ability for our staff members to submit Service Requests to our IT Dept using SharePoint. A few WinXP Pro users are unable to submit the SR - their IE8 browser simply hangs at the point of clicking OK from
the New Item screen - no error message appears. Majority of users do not experience this problem. We are running SharePoint with Search Server 2008 on top of Windows Server 2003 R2.
According to your description, you said only a few user has these issue. So, I suspect this is some plugin is installed on their IE caused this. After my search, there is an article is similar
to you. You can refer to the following link.
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