How to get rid of this error message "no method named Column in class edu.mit.appinventor"

Tutorials and Guides
#1
  1. export aia
  2. open it with 7-Zip or winRAR
  3. go to the affected ScreenX.scm: right mouse click: “Edit” (or: F4)
  4. remove “Column”:“X” and “Row”:“Y”
  5. close Editor & 7-Zip / winRAR

No need to copy or rename anything. See the solution from @Svetlana_GREGOIRE : Newbie here...need a little help invoke: no method named `Column' in class edu.mit.appinventor

App Crashed when open screen Only
Newbie here...need a little help invoke: no method named `Column' in class edu.mit.appinventor
#6

Since this error has only occurred for a few days and I have never encountered it before, I assume that it is related to the last AI2 update. @ewpatton

#7

I went through all the versions of App Inventor from nb181 (when multiselect was released) through nb183b (released yesterday). I was able to reproduce this issue in nb183, but not nb183a. I did quite a bit of work between nb183 and nb183a on the multiselect functionality based on reports from @SteveJG and @ABG. The bug was that having the screen selected along with dragging a component into a TableArrangement would result in the Screen inheriting the column and row properties erroneously. I’ve submitted an additional patch that will remove these properties when the project loads (pending review).

Regards,
Evan

FAQ Section: App Inventor Issues
#8

(added to FAQ)

#9

This guide is / should be obsolte with the last update (nb183c):