I'm using DNN 4.3.2 and haven't had any problems until recently uploading files with the File Manager; for the past few days I've been struggling to understand why I can't upload any files (I've tried different types). Logging in as a portal admin or host makes no difference. The file types are included under host settings and the template is just DNN default. In File Manager, Administrators have write permissions for all folders.

Does anyone have any suggestions?

Thanks

I've done that now. The upgrade appears to have gone successfully. However, when I try to view the contents of one of the File Manager folders in one of the Portals, I get the following error:

An error has occurred.
DotNetNuke.Services.Exceptions.PageLoadException: Value cannot be null. Parameter name: format ---> System.ArgumentNullException: Value cannot be null. Parameter name: format at System.String.Format(IFormatProvider provider, String format, Object[] args) at DotNetNuke.Modules.Admin.FileSystem.FileManager.BindFileList() at DotNetNuke.Modules.Admin.FileSystem.FileManager.DNNTree_NodeClick(Object source, DNNTreeNodeClickEventArgs e) at DotNetNuke.UI.WebControls.DnnTree.OnNodeClick(DNNTreeNodeClickEventArgs e) at DotNetNuke.UI.WebControls.TreeNode.Click() at DotNetNuke.UI.WebControls.DnnTree.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 ---

All the other folders show their contents without throwing this error.