https://community.esri.com/t5/arcgis-online-questions/there-was-an-error/m-p/1240999#M49355 <P>That error message is indeed strange but has a link on the support site.</P><P>It may not be the solution but give it try anyway</P><P><A href="https://support.esri.com/en/technical-article/000024402" target="_blank">Problem: Unable to view data on the Data tab in ArcGIS Online (esri.com)</A></P> Wed, 14 Dec 2022 10:53:00 GMT DanPatterson 2022-12-14T10:53:00Z https://community.esri.com/t5/arcgis-online-questions/there-was-an-error/m-p/1240981#M49353 <P>I am trying to append data from a CSV file to a layer and I keep getting an error message, there was an error. What could be the problem?</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="DianaKyalo_0-1671006947826.png" style="width: 400px;"><img src="https://community.esri.com/t5/image/serverpage/image-id/58482iF05248A8A3F76AA1/image-size/medium?v=v2&amp;px=400" role="button" title="DianaKyalo_0-1671006947826.png" alt="DianaKyalo_0-1671006947826.png" /></span></P><P>&nbsp;</P> Wed, 14 Dec 2022 08:36:56 GMT https://community.esri.com/t5/arcgis-online-questions/there-was-an-error/m-p/1240981#M49353 DianaKyalo 2022-12-14T08:36:56Z https://community.esri.com/t5/arcgis-online-questions/there-was-an-error/m-p/1240999#M49355 <P>That error message is indeed strange but has a link on the support site.</P><P>It may not be the solution but give it try anyway</P><P><A href="https://support.esri.com/en/technical-article/000024402" target="_blank">Problem: Unable to view data on the Data tab in ArcGIS Online (esri.com)</A></P> Wed, 14 Dec 2022 10:53:00 GMT https://community.esri.com/t5/arcgis-online-questions/there-was-an-error/m-p/1240999#M49355 DanPatterson 2022-12-14T10:53:00Z