I'm working on a migration from SPS 2003 to Moss and as part of the work we are restructuring the portal so that the content is split out into multiple Site Collections. The existing site has one site collection with 45GB of data in it.
Once the site collection is migrated I'm exporting and importing the subsites into new site collections to achieve this, but part way through the import of one site, the import failed and the log files showed: (NB I've shortened the folderpath)
[11/4/2008 7:31:45 AM]: Progress: Importing Folder /Corporate/IT/Document Library/.../foldername_files.
[11/4/2008 7:31:45 AM]: FatalError: Object reference not set to an instance of an object.
at Microsoft.SharePoint.Deployment.FolderSerializer.SetObjectData(Object obj, SerializationInfo info, StreamingContext context, ISurrogateSelector selector)
at Microsoft.SharePoint.Deployment.XmlFormatter.ParseObject(Type objectType, Boolean isChildObject)
at Microsoft.SharePoint.Deployment.XmlFormatter.DeserializeObject(Type objectType, Boolean isChildObject, DeploymentObject envelope)
at Microsoft.SharePoint.Deployment.XmlFormatter.Deserialize(Stream serializationStream)
at Microsoft.SharePoint.Deployment.ObjectSerializer.Deserialize(Stream serializationStream)
at Microsoft.SharePoint.Deployment.ImportObjectManager.ProcessObject(XmlReader xmlReader)
at Microsoft.SharePoint.Deployment.SPImport.DeserializeObjects()
at Microsoft.SharePoint.Deployment.SPImport.Run()
Initially I took a look at the folder in the document library referenced on the last line before the error and found that there was nothing in it, which seemed a little odd. It transpired that the users have saved web pages in the folder above which creates a .htm file for the page and a subfolder with the ending _files, and also that although the folder showed no files when accessed via the browser, the web page saved in the folder above it was referencing images in the _files folder. I wondered if it was something to do with the length of the folder path or one of the characters in it, so I tried to rename it, but this gave me the following error message:
Server Error in '/' Application.
You cannot copy or move a thicket file. To change the file name or create a copy of the file, open the file and save as to a new name.
Some googling led to the following post. It would appear that creating a folder with the ending _files causes SharePoint to think that the folder is a system folder. Some further playing around led to the discovery that if you open the folder in the browser where it shows no files and then select to open the folder with Windows Explorer the contents of the folder are visible. But if you navigate up within Windows Explorer you are then unable to see the folder at all.
Anyhow my solution - delete the folder and run the export and import again. Let's hope it works this time!