error 7777 during execution

[Aussiebear]

This error typically occurs when:

1. If you trying to set the ListIndex property of a control that doesn't allow it, or when there's no item selected, or the index is out of bounds. While ListIndex is read/write for UserForm ListBoxes (meaning you can set it to select an item), it can be read-only in certain contexts or for certain types of controls (e.g., in MS Access sometimes, or for some older Excel control types). Given that you continue to post in the Access sub forum then perhaps this may be the issue.
2. You are still using an ActiveX ListBox on a worksheet, but now attempting to manipulate ListIndex in a way it doesn't support, or you've misunderstood how ListIndex works for selection.

So let's break down the likely causes and solutions, especially if you've attempted to switch to a UserForm, or are trying to use ListIndex with your existing setup:
Common Scenarios for "Invalid Use of Property ListIndex":

• Trying to Set ListIndex When No Item is Selected or List is Empty:
  
  • If ListBox1.ListCount is 0 (the ListBox is empty), trying to set ListBox1.ListIndex = 0 or any other value will cause this error because there are no items to select.
  • Similarly, if the ListBox is populated but nothing is selected (ListBox1.ListIndex would be -1), and they try to manipulate it directly without first selecting an item (e.g., Me.ListBox1.ListIndex = Me.ListBox1.ListIndex + 1 when ListIndex is -1), it can fail.
  
  
• ListIndex on a Multi-Select ListBox (Incorrect Selection Method):
• If the MultiSelect property of the ListBox is set to fmMultiSelectMulti (allowing multiple selections), you generally cannot use ListBox1.ListIndex = X to select an item. Instead, you need to use the Selected array property: ListBox1.Selected(X) = True. If you are trying to set ListIndex directly on a multi-select ListBox, this error will occur.
• While we are guideing you towards UserForms, a typo or referring to a different type of control that looks like a ListBox but isn't, could cause this.
• If the code attempting to set or use ListIndex runs before the ListBox has been populated with items, then ListCount will be 0, and ListIndex will be -1, leading to the error when trying to access or set it.
• Incorrect Object Reference (Less likely now, but possible):
• List Not Populated Yet:

How to Help us to help you to Debug and Solve:
1. Confirm the ListBox Type and Context (Again!):

• Can you confirm: "Is this ListBox on a UserForm or directly on an Excel worksheet?"
• If it's on a UserForm, excellent. If it's on a worksheet, the previous advice (in your previous thread) about using a UserForm still stands as the primary solution.

2. Check the MultiSelect Property:

• Crucial Step: Can you go to the Properties window for your ListBox (on the UserForm).
• Find the MultiSelect property.
• If MultiSelect is set to 1 - fmMultiSelectMulti or 2 - fmMultiSelectExtended: This is almost certainly the cause.
• Solution for Multi-Select: They cannot use ListBox1.ListIndex = X. They must use ListBox1.Selected(X) = True.

3. Check for Empty ListBox:

• You could try and insert a debug line before the line causing the error:

Debug.Print "ListBox1.ListCount: " & Me.ListBox1.ListCount
        Debug.Print "ListBox1.ListIndex: " & Me.ListBox1.ListIndex
        Stop ' This will pause execution so they can see the Immediate Window (Ctrl+G)

• If ListCount is 0, then the list is empty, and they need to ensure it's populated before trying to manipulate ListIndex.
• If ListIndex is -1 and they're trying to add to it, that's also an issue.

4. Review the Exact Line of Code Causing the Error:

• Can you indicate the exact line of code that the debugger highlights when the error occurs. This is the most direct way to pinpoint the problem.This error typically occurs when:
  
  1. Are you trying to set the ListIndex property of a control that doesn't allow it, or when there's no item selected, or the index is out of bounds. While ListIndex is read/write for UserForm ListBoxes (meaning you can set it to select an item), it can be read-only in certain contexts or for certain types of controls (e.g., in MS Access sometimes, or for some older Excel control types). Please test for the afore mentioned scenarios.
  2. Are you still using an ActiveX ListBox on a worksheet, but now attempting to manipulate ListIndex in a way it doesn't support, or you've misunderstood how ListIndex works for selection.
  
  Let's break down the likely causes and solutions, especially if you've attempted to switch to a UserForm as previousily suggested, or are trying to use ListIndex with their existing setup:
  Common Scenarios for "Invalid Use of Property ListIndex":
  
  
  • Trying to Set ListIndex When No Item is Selected or List is Empty:
    
    • If ListBox1.ListCount is 0 (the ListBox is empty), trying to set ListBox1.ListIndex = 0 or any other value will cause this error because there are no items to select.
    • Similarly, if the ListBox is populated but nothing is selected (ListBox1.ListIndex would be -1), and they try to manipulate it directly without first selecting an item (e.g., Me.ListBox1.ListIndex = Me.ListBox1.ListIndex + 1 when ListIndex is -1), it can fail.
    
    
  • ListIndex on a Multi-Select ListBox (Incorrect Selection Method):
  • If the MultiSelect property of the ListBox is set to fmMultiSelectMulti (allowing multiple selections), you generally cannot use ListBox1.ListIndex = X to select an item. Instead, you need to use the Selected array property: ListBox1.Selected(X) = True. If you are trying to set ListIndex directly on a multi-select ListBox, this error will occur.
  • While we are guideing you towards UserForms, a typo or referring to a different type of control that looks like a ListBox but isn't, could cause this.
  • If the code is attempting to set or use ListIndex runs before the ListBox has been populated with items, then ListCount will be 0, and ListIndex will be -1, leading to the error when trying to access or set it.
  • Incorrect Object Reference (Less likely now, but possible):
  • List Not Populated Yet:
  
  Help us to help you Debug and Solve:
  1. Confirm the ListBox Type and Context (Again!):
  
  
  • Could you confirm: "Is this ListBox on a UserForm or directly on an Excel worksheet?"
  • If it's on a UserForm, excellent. If it's on a worksheet, the previous advice about using a UserForm still stands as the primary solution.
  
  2. Check the MultiSelect Property:
  
  
  • Crucial Step: Please go to the Properties window for your ListBox (on the UserForm).
  • Find the MultiSelect property.
  • If MultiSelect is set to 1 - fmMultiSelectMulti or 2 - fmMultiSelectExtended: This is almost certainly the cause.
  • Solution for Multi-Select: They cannot use ListBox1.ListIndex = X. You must use ListBox1.Selected(X) = True.
  
  3. Check for Empty ListBox:
  
  
  • Could you please try to insert a debug line before the line causing the error:
  
  
  

  Debug.Print "ListBox1.ListCount: " & Me.ListBox1.ListCount
  Debug.Print "ListBox1.ListIndex: " & Me.ListBox1.ListIndex
  Stop ' This will pause execution so you can see the Immediate Window (Ctrl+G)

  • If ListCount is 0, then the list is empty, and they need to ensure it's populated before trying to manipulate ListIndex.
  • If ListIndex is -1 and you're trying to add to it, that's also an issue.
  
  4. Review the Exact Line of Code Causing the Error: As Gasman has suggested a presentation of your current code would be helpful.
  
  
  • We ask you for the exact line of code that the debugger highlights when the error occurs. This is the most direct way to pinpoint the problem.