Here is the solution from the Microsoft IE team.

Please use the instruction below to disable the pop up blocker message via Registry. I have tested it and it works

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• Resolution:

Reg key provided by the IE team

Create a dword reg key “TabProcGrowth” under:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN

AND

HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main

TabProcGrowth (dword 32-bit) with value = 0

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Hani