Thank you for posting in the answers forum! I'm sorry to hear you are having issues with trying to re-connect your Slingbox. I understand you said you have a bridge to your DVR. Are you speaking of a wireless bridge? Is, that will need to be connected to your router and not the DVR. Also, being that it has not been connected for a while, I would recommend hard resetting the Slingbox to factory settings and go to setup.slingbox.com to go through the online setup again.
Below is a link to an article that tells you how to reset the Slingbox to factory settings:
Hope this helps!
The Sling Moderation Team