Note that typically the reason this happens is that there is code behind the datasheet form that modifies properties on the form or controls (e.g. Textbox.Locked). Access intends to save the datasheet column widths without saving the properties changed in code, and that process was not working as expected. We are planning to fix this, but in the meantime, you may be able to work around this if you can avoid changing form/control properties in code (e.g. by using Conditional Formatting instead)
An error occurred while saving the commentAnonymous commented
Was able to fix this in AC2016 by changing the tab order of the controls in the subform - much easier fix.