They are several things wrong with Kryst51's code:
AllowEditions is incorrect; it should be AllowEdits.
Me.Forms.AllowDeletions = True
is also incorrect. The proper syntax would be
Me.AllowDeletions = True
without the Form being in there.
Setting the form properties AllowAdditions, AllowEdits, etc to No in the Property pane makes changing them back, after setting them to Yes in code, unnecessary in the Form_Close event. These properties will be 'reset' each time the form opens, automatically.
Making these corrections, Kryst51's suggestions will work, assuming you want all records to be editable once the button is clicked.
If, on the other hand, you only want the current record to be editable, with the form returning to Read-Only on moving to another record, you need to set the appropriate "Allow" properties to No in the Form_Current event.
Which situation suits your needs, and do you want to also control the ability to add new records with this button as well or just prevent editing of existing records?
Linq ;0)>