How do I resolve the ECM error I received when trying to attach a document in CORE? (07/2018)

You will want to make sure that your file is no larger than 2mb.  If your file is 2mb or less,  you will want to clear your browser history and close out all of your browser windows prior to logging back into CORE to retry uploading the document.  If you're still seeing the ECM error, you will want to rename the file and try to upload again.