Run-time error '1004': Unable to set the Hidden property of the Range class

Hi there-

I'm new to this forum but hopefully someone can help me out.

- I have this Excel Sheet with hidden cells (IF Conditions) that opens depending if you answer YES/NO.

- I also have Grouped Cells that will expand or collapse if you click on the left side slider.

- I need to protect both worksheets (which I did and only unlocked the cells where people are required to respond Yes/No or type in a particular cell.

My issue:
- Every time I save and then open the Excel file I get "Run-time error '1004' - Unable to set the Hidden property of the Range class"
- Since I need to protect the worksheets none of the hidden cells (IF Conditions) will work and I can't collapse any of the Grouped Cells.

I tried adding some VBA Code that I found but doesn't seem to work...

Any help would be great!

Thanks Jeff for your reply.

So basically this is what I'm doing:
1. I unprotected the worksheet

2. I created all of the IF Conditions that hide and unhide cells based upon the responses. (this is in VBA Project)

3. I grouped certain rows so they can collapse or expand.

4. I went to VBAProject and created a Module (I found it in this Forum) so that when I protect my worksheet the grouped rows will collapse and expand:
Sub allowGroup()
Dim mySheet As Worksheet
Set mySheet = Application.ActiveSheet
Dim myPW As String
myPW = Application.InputBox("Type one Password to protect your worksheet:", "allowGroup", "", Type:=2)
mySheet.Protect Password:=myPW, Userinterfaceonly:=True
mySheet.EnableOutlining = True
End Sub

5. I ran the Sub/UserForm and added a pwd myPW and exited out of VBA Project.

6. I can see that the worksheet is protected.

7. The worksheet allows me to expand and collapse the protected grouped rows AND my IF Conditions open up the hidden rows.

Now here is what's frustrating me...
8. I close the Excel sheet.

9. I open the Excel sheet.

10. I try to expand one of the grouped rows and I get the following message: "You cannot use this command on a protected sheet. To use this commend, you must first unprotect the sheet...." Since many users will be using this worksheet, I was hoping to avoid them unprotecting the worksheet in order to see the rows since there's a lot of information.

11. When I click one of the Yes/No boxes, I get the following message: "Run-time error '1004': Unable to set the Hidden property of the Range class"

So basically are you saying that:
a. There's no Coding that would allow me to group ad protect rows?

b. Is my VBAProject need to be edits so my IF Conditions will work when I protect the worksheet?

Thanks again!