Hello, I'm new to dnn and hoping someone can help me. I'm working on an existing site that is having a lot of file manager issues. The dnn version is 04.09.00.

I'm logged in as host, going to Admin | File Manager (Host | File Manager has these same issues):

Under Standard - file system, if I try to add a folder, I get this error:
A critical error has occurred.
Object reference not set to an instance of an object.

If I click refresh, I get:
An error has occurred.
DotNetNuke.Services.Exceptions.PageLoadException: Object reference not set to an instance of an object. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Modules.Admin.FileSystem.FileManager.BindFileList() in D:\blahAdmin\\Files\FileManager.ascx.vb:line 393 at DotNetNuke.Modules.Admin.FileSystem.FileManager.lnkRefresh_Command(Object sender, CommandEventArgs e) in D:\blah\Admin\Files\FileManager.ascx.vb:line 1848 at System.Web.UI.WebControls.LinkButton.OnCommand(CommandEventArgs e) at System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---

If I expand the portal root folder on left, and click any folder, I get this error:
Error: File Manager is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Object reference not set to an instance of an object. ---> System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Modules.Admin.FileSystem.FileManager.GeneratePermissionsGrid() in D:\blah\Admin\Files\FileManager.ascx.vb:line 576 at DotNetNuke.Modules.Admin.FileSystem.FileManager.Page_Load(Object sender, EventArgs e) in D:\Blah\Admin\Files\FileManager.ascx.vb:line 1116 --- End of inner exception stack trace ---

If I click Synchronize Files I get this error:
A critical error has occurred.
Object reference not set to an instance of an object.

If I click Synchronize and Recursive, it'll go for around 90 seconds and then get an error (worried what this is doing so would rather not run it again).

A folder created via FTP did show up after the recursive synchronize, but I can't click it to synchronize other files uploaded via FTP. The site admins have been using the editor's upload file control and there's another built in one that's being used - I just added ftp recently.

So as you can see, having issues and I'm not sure where to start. The ntfs permissions are all full control Network Service so am guessing something is up w/ dnn's folder permissions instead. I'm also not sure if the recursive synchronize to error is causing any additional issues. The DotNetNuke.Services.FileSystem.SynchronizeFileSystem, DOTNETNUKE is not enabled.

This site has several thousand users, and lots of customization and third party modules so not a site I feel real comfortable tinkering with a whole lot. Thanks for any help!