When I want to sign in to desktop manager, it says I must sign in to continue, one I do so, the message pops up again, asking me to sign in.
My apps also say I require a serial number for my trial has expired, but I purchased the CC.
If you have CC, the programs asking for serial number is a conectivity issue. See if this helps: http://helpx.adobe.com/x-productkb/policy-pricing/activation-network-issues.html
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