Code to unhide all Excel worksheets within a workbook.

IMW_UnHide_Sheets.vb

' PASTE INTO IMMEDIATE WINDOW
for each sh in worksheets: sh.visible=true: next sh

UnHide_All_Sheets.vb

' MACRO to unhide all workbook worksheets
Sub Unhide_All_Sheets()
    Dim wks As Worksheet
 
    For Each wks In ActiveWorkbook.Worksheets
        wks.Visible = xlSheetVisible
    Next wks
End Sub

UnHide_All_Sheets_Count.vb

' MACRO to unhide all sheets and display count
Sub Unhide_All_Sheets_Count()
    Dim wks As Worksheet
    Dim count As Integer
 
    count = 0
 
    For Each wks In ActiveWorkbook.Worksheets
        If wks.Visible <> xlSheetVisible Then
            wks.Visible = xlSheetVisible
            count = count + 1
        End If
    Next wks
 
    If count > 0 Then
        MsgBox count & " worksheets have been unhidden.", vbOKOnly, "Unhiding worksheets"
    Else
        MsgBox "No hidden worksheets have been found.", vbOKOnly, "Unhiding worksheets"
    End If
End Sub

UnHide_All_Sheets_Named.vb

'Unhide worksheets with a specific word in the sheet name
Sub Unhide_Sheets_Contain()
    Dim wks As Worksheet
    Dim count As Integer
 
    count = 0
 
    For Each wks In ActiveWorkbook.Worksheets
        If (wks.Visible <> xlSheetVisible) And (InStr(wks.Name, "report") > 0) Then
            wks.Visible = xlSheetVisible
            count = count + 1
        End If
    Next wks
 
    If count > 0 Then
        MsgBox count & " worksheets have been unhidden.", vbOKOnly, "Unhiding worksheets"
    Else
        MsgBox "No hidden worksheets with the specified name have been found.", vbOKOnly, "Unhiding worksheets"
    End If
End Sub