Unable to download authentication module, please try again later.

Scenario: Your Starcraft 2 game is showing this error:
"Unable to download authentication module, please try again later."

We would like to thank Daviash for this awesome Zeratul wallpaper.

Here is what you do (Avast users):
a) Open the user interface (UI)

b) Go to Real-Time Shields (Tab on left side)

c) Go to Expert Settings

d) Go to Exclusions

e) At the bottom of the list, there will be an empty box to type in.

Type C:\ProgramData\Blizzard Entertainment\Battle.net\Cache\36\b2\*.auth and then hit Enter.

f) Make sure all 3 checkboxes are marked.

g) Click OK and then Exit.

We would like to thank Curandera for this work-around.

For all other anti-virus programs, just analyze the Avast steps and apply the same exceptions/exclusions to your AV. This allows BattleNet to connect to Activision Blizzard's servers and to download the authentication module.

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