It took me a long time to get my DNN site to work and then I just had to mess with the skins. now I get

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DotNetNuke.Services.Exceptions.PageLoadException: Value cannot be null. Parameter name: type ---> System.ArgumentNullException: Value cannot be null. Parameter name: type at System.Activator.CreateInstance(Type type, Boolean nonPublic) at DotNetNuke.Framework.Reflection.CreateObject(String TypeName, String CacheKey, Boolean UseCache) at DotNetNuke.Framework.Reflection.CreateObject(String ObjectProviderType, String ObjectProviderName, String ObjectNamespace, String ObjectAssemblyName, Boolean UseCache) at DotNetNuke.Modules.NavigationProvider.NavigationProvider.Instance(String FriendlyName) at DotNetNuke.UI.Skins.NavObjectBase.InitializeNavControl(Control objParent, String strDefaultProvider) at DotNetNuke.UI.Skins.Controls.TreeViewMenu.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at DotNetNuke.Framework.DefaultPage.Page_Init(Object sender, EventArgs e) at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.Page.OnInit(EventArgs e) at DotNetNuke.Framework.PageBase.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---

time to delete and start over

I'm afraid I can't help with your problems, but I can sympathise greatly with the frustration... and the pain of facing another rebuild from scratch.

One of the things every DNN user needs to develop early on is a solid backup and restore procedure. This has to be so quick and easy to carry out that you are successfully motivated to do it regularly throughout the day whilst messing with or working on your sites.

Working with DNN takes so much time that you eventually realise you can't afford to rebuild from scratch over and over again... and that's the point where you realise you have to improve your work procedures.

If you work locally, then it's pretty easy to sync folders and make backups, but if you work on a remote host then things might be harder. On my current host it only takes me a couple of minutes to zip up the file system and backup the database and I do this prior to any work I do and after I've carried out some work successfully.

In addition, I note every single modification step I make to any item in my portal. It's simply not possible to offer DNN based services without good processes. I've seen some horrific failures around lately and narrowly avoided one myself recently. This has caused me to upgrade my hosting account for better access and speed and also to ensure I don't lull myself into feeling secure just because things go well for a period.

Backing up is still not ideal. Being a well-trained expert in all things DNN-related would be better... but then I probably wouldn't be using DNN if I were that capable... so backup and restore is the only way.

I'm posting in an effort to save others who are starting out a lot of time and energy.

Regards,
Rob

$.02 =

For production changes I often copy my skin/container folder and paste it in place with a different name then create a new non-public page and apply the copied skin/container.

Then I use my html/css editor directly on the copied ascx & css files, save my changes refresh my page, etc.

When I'm happy I'll replace the original files with the altered ones and it's fairly seemless, all the while working with an non-public page on a production site. I ofen do this and it works well for me because I can visualize my changes with real content.

The only times I sweat full backups when I do this is when I'm introducing new skin objects or touching something besides the file copies I'm working with.

Absoutely not dissing the need for careful backups; but one of the cool things about dnn is that I can tweak the design without creating multiple instances, requesting irregular backups from the server group, or really touching the content or the application itself  (n-tier right?).

Once again: I am not disputing the need for careful backups and I fully acknowledge that they are the a good idea prior to and after most changes; but they're not the only 'roll-back' method for simple skin work or experimentation.