I've deployed a fresh install of DotNetNuke 5.1.2 with all the default settings, and everything looks good except the module drop-downs. When I hover over them, the spinning wheel starts spinning and the drop-down never appears. (This is the drop-down list that includes Edit, Settings, Move, etc.). This happens with any module, including Admin and Host modules used for site management.
In Firefox, the spinning wheel just continues to spin until I browse to another page. In IE, I get an error: (FWIW, I also get the same issue in Google Chrome).
Webpage error details
User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; WOW64; Trident/4.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.5.21022; .NET CLR 3.5.30729; OfficeLiveConnector.1.4; .NET CLR 3.0.30729; OfficeLivePatch.1.3)
Timestamp: Fri, 25 Sep 2009 02:20:56 UTC
Message: Sys.ArgumentException: Cannot deserialize. The data does not correspond to valid JSON.
Parameter name: data
I've installed numerous instances of DNN, from version 2.x up until 4.9. This is my first attempt at 5.x, and my first installing on a Vista machine (the others were XP Pro, and Windows Server 2003). My new dev box is Vista Home Premium.
Any ideas why this is happening? I know it's got to be something simple that I'm missing, but I've been wracking my brain for hours trying to figure it out. I'm hoping one of the smart folks here can help me out.