The form cannot be submitted to the Web server either because your computer is offline or because the host server is currently unavailabl. If this problem persists, contact your network administrator.

Hi,

When the page is submitted for approval by using SharePoint OOTB Page Approval Workflow, it takes quite long time and prompt error message as below.
"The form cannot be submitted to the Web server either because your computer is offline or because the host server is currently unavailable.
If this problem persists, contact your network administrator."

It only happens in Internet Explorer version 8 and 9. IE version below 8 is not used in environment.
But it is working in Firefox.
Please help me on how to fix this issue.

Thanks.