What is this strange "J" icon in Excel-file

Question

Our customer reports that Excel crashes on their computer, when they attempt to open the Excel-file. I can open it just fine. However, there are a few oddities in there that I'm not familiar with.

I assume that the following J-icon is some sort of placeholder for a missing control. It seems attached to the column, so if I resize the C column, the J-icon still sits at the beginning of the D-column. If I attempt to delete all contents of the sheet without deleting the sheet itself, the icon stays. I can't select the icon itself.

Also, there are a ton of "Forms.HTML:Hidden.1" controls in one of the sheets. I've seen a lot of questions regarding this, but none explaining how they ended up there. The "Properties" window shows no properties for these controls.

I believe that removing these oddities may allow the customer to open the sheets once again.

But how do I delete them and what purpose could they serve?

Update:

The workbook was shared. Unsharing it allowed me to delete the objects.

Answer 1

I believe the J-icon represents an embedded JavaScript object. The steps in this link should help you get rid of those objects.

In short, press F5, click the Special... button, and select Objects. That will allow you to select and delete the objects embedded in the worksheet.

If this doesn't work, you can try using a macro to get rid of them (steps from this forum). Right-click on the sheet tab at the bottom and click "View Code". Copy the following and paste it into the editor:

Sub Shapes1()
'Delete all Objects except Comments
    On Error Resume Next
    ActiveSheet.DrawingObjects.Visible = True
    ActiveSheet.DrawingObjects.Delete
    On Error GoTo 0
End Sub

Press Alt+Q to close and return to Excel, open the macros window with Alt+F8, select the new macro (Shapes1), and run it.