Control Panel/Webmail logon problem

[leigh]

I have many clients with this problem. They can access their websites fine. But when they try to access their webmail, or their Control Panel (either through https or http), they get "The Page Cannot Be Displayed..." error. They can access it from another computer, but not from all. Any suggestions? I've poured over the forums for the past HOURS looking for an answer. Any help is greatly appreciated as we have been battling this for days now... thanking you in advance.

[Peoplespaces]

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