This is driving me batty.
I'm moving a large quantity of files (documents - .doc, .pdf, .xls) from one subsite to another in Sharepoint 2013. Since we want to preserve the metadata, I'm doing so via Site Contents and Structure (checking files and selecting Actions > Move). It runs smoothly for a while, then I start getting this error. Sometimes simply reloading or trying again will work, sometimes I have to log out or clear my cache, sometimes switching browsers, sometimes just moving on to a different folder.. until eventually I get the error every time. But if I wait several hours, it will start working again. Every time I think I've figured out what's causing the error (file size too large, destination folder too full, something in my cache...), something happens to toss that theory out the window. I've googled extensively and not found anything useful. Please help.
Despite being inconsistently triggered, the error itself is the same each time.
The current operation could not be completed. Try again, or contact your system administrator.
Object reference not set to an instance of an object.
You may re-try the operation, and you may need to clean up the half-created data first before re-trying. If the problem persists, please contact your system administrator.
Correlation ID: b1d45b9e-0eab-a03a-1c95-1245c7894e01
Date and Time: 4/9/2018 10:55:16 AM
<error><message>Object reference not set to an instance of an object.</message><full>System.NullReferenceException: Object reference not set to an instance of an object. at Microsoft.SharePoint.Library.SPRequest.GetFileAndFolderProperties(String bstrUrl, String bstrStartUrl, ListDocsFlags ListDocsFlags, Boolean bThrowException, Int32& phrStatus, Object& pvarFiles, Object& pvarDirs, UInt32& pdwNumberOfFiles, UInt32& pdwNumberOfDirs) at Microsoft.SharePoint.SPWeb.GetFileOrFolderProperties(String strUrl, ListDocsFlags listDocsFlags, Boolean throwException, SPBasePermissions& permMask) at Microsoft.SharePoint.SPFolder.PropertiesCore(Boolean throwException) at Microsoft.SharePoint.SPFolder.ThrowIfNullProperties() at Microsoft.SharePoint.SPFolder.get_WelcomePage() at Microsoft.SharePoint.Publishing.Internal.WebControls.SMPickerValidator.SMValidateMove(ObjectSerializer sourceObj) at Microsoft.SharePoint.Publishing.Internal.WebControls.SMPickerValidator.ValidateObjects(ObjectSerializer sourceObject, ObjectSerializer targetObject, Boolean validateType, Boolean validateBranch, Boolean validateMove) at Microsoft.SharePoint.Publishing.Internal.WebControls.SMPickerValidator.ValidateOperation(SPSite contextSite, String sourceSmtObjectIds, String targetObjectId, Boolean validateType, Boolean validateBranch, Boolean validateMove) at Microsoft.SharePoint.Publishing.Internal.WebControls.MoveItems.IsValidMove() at Microsoft.SharePoint.Publishing.Internal.WebControls.MoveItems.DoWork() at Microsoft.Office.Server.Diagnostics.FirstChanceHandler.ExceptionFilter(Boolean fRethrowException, TryBlock tryBlock, FilterBlock filter, CatchBlock catchBlock, FinallyBlock finallyBlock)</full><customData></customData></error>