This file was created in 2010, no issue with a previous version of Project.
I can add a column using the “Add New Column” functionalitly (in the rightmost column), but cannot add any new columns anywhere by right clicking on a column header and selecting “Insert Column” on the dropdown menu. I can hide a column by selecting the “Hide Column” on the dropdown menu. And it’s only on this one file, not on other files.
I also tried adding “Insert Column” to the quick access toolbar, and it doesn’t work for this file only (works fine on other files).
I also made sure that “edit directly in cell” was selected in the Edit options.
It’s apparently something with just this file. I tried exporting to xml and reading back in, but the problem persisted.
Any other ideas on how to deal with this would be much appreciated!