Hi @Brian GormleyWhich version of Office are you using?
If "even in new blank workbooks", VBE cannot be opened with such error message, I suggest you clear the Excel cache.
• Close Excel, open Finder.
• Press Command + Shift + G, input “~/Library/Containers”, move com.microsoft.Excel to desktop.
• Press Command + Shift + G, input “~/Library/Preferences”, move com.microsoft.office.plist to desktop.
• Open Excel, and check if VBE can be opened correctly.
If the problem remains, please try creating a new user profile in Mac then use the new one to open Excel to check if the issue is caused by account settings and preferences.
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