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WebPart has empty viewstate on postback

Posted By:      Posted Date: August 31, 2010    Points: 0   Category :ASP.Net
I have a simple weather web part in the form of a user control.  This usercontrol has an update panel and a textbox to allow the user to enter in a zip code/ city etc and an ok button.  The problem comes in when the webpart is added or dragged outside of Zone 1.  If this webpart remains in Zone 1 everything is fine.  If it is in Zone 2 or 3 after entering a zip code and hitting ok and posting back the value of the textbox is always blank.  It seems like the viewstate is cleared or the control is loading for the first time.  I have checked the Page.IsPostBack property and it is indeed True.  What would cause my control to loose the value entered in the textbox only when it resides outside of Zone 1?

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