iCloud Web App Plugin wants to install everytime

Hello everybode,

The following Problem:

I sign in at www.iCloud.com. Then I'm asked to install the "icloud Web App Plugin". When doing so, everything seems to be fine.

But the next time, I signe in, the same thing: Do you want to install the "iCloud Web .."

It seems to me, that this Add-On cannot be installed on my Windows 7 PC.

Any solution? Thanks a lot

Morgandalf