If the answer to the above is yes, then this should work:

Sub Mail_workbook_Outlook_1()
    Dim OutApp As Object
    Dim OutMail As Outlook.MailItem
    Dim signature As String
    
    EmailTo = Worksheets("E-mail Sheet").Range("B26")
    
    Dim Found As Range
    
    EmailTo = Worksheets("E-mail Sheet").Range("B26")
    
    Set Found = Sheets("Current Clients").Columns("C").Find(What:=Sheets("E-mail Sheet").Range("A26").Value, _
        LookIn:=xlValues, LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, MatchCase:=False)
                                               
    If Not Found Is Nothing Then
        If IsEmpty(Found.Offset(, -2)) = False Then
            If MsgBox(Range("A26").Value & vbNewLine & vbNewLine & "An item request has  been sent on: " & Found.Offset(, -2).Value & vbNewLine & _
            "Items were recieved on: " & Found.Offset(, -1).Value & vbNewLine & vbNewLine & "See Current Clients page for more information" & vbNewLine & vbNewLine _
            & "Do you want to continue?", vbYesNo) = vbNo Then
                Exit Sub ' stop macro if user selects No
            End If
        End If
    End If

    
    Set OutApp = CreateObject("Outlook.Application")
    Set OutMail = OutApp.CreateItem(0)

    On Error Resume Next
    With OutMail
        .display
        signature = .htmlBody
        .To = Worksheets("E-mail Sheet").Range("B26")
        .CC = Worksheets("E-mail Sheet").Range("B19")
        .BCC = ""
        .Subject = "Updating Credit File - " & Worksheets("E-mail Sheet").Range("D26")
        .htmlBody = "Dear " & Worksheets("E-mail Sheet").Range("C26") & "," & "<br><br>" & _
        "We are requesting the following information to bring your credit file up to date." & "<br><br>" & Worksheets("E-mail Sheet").Range("B2") _
        & Worksheets("E-mail Sheet").Range("C2") & vNewLine & vbNewLine & Worksheets("E-mail Sheet").Range("B3") & Worksheets("E-mail Sheet").Range("C3") _
        & "<br><br>" & Worksheets("E-mail Sheet").Range("B4") & Worksheets("E-mail Sheet").Range("C4") & "<br><br>" & Worksheets("E-mail Sheet").Range("B5") _
        & Worksheets("E-mail Sheet").Range("C5") & "<br><br>" & Worksheets("E-mail Sheet").Range("B6") _
        & Worksheets("E-mail Sheet").Range("C6") & "<br><br>" & Worksheets("E-mail Sheet").Range("B7") _
        & Worksheets("E-mail Sheet").Range("C7") & "<br><br>" & Worksheets("E-mail Sheet").Range("B8") _
        & Worksheets("E-mail Sheet").Range("C8") & "<br><br>" & Worksheets("E-mail Sheet").Range("B9") _
        & Worksheets("E-mail Sheet").Range("C9") & "<br><br>" & Worksheets("E-mail Sheet").Range("B10") _
        & Worksheets("E-mail Sheet").Range("C10") & "<br><br>" & Worksheets("E-mail Sheet").Range("B11") _
        & Worksheets("E-mail Sheet").Range("C11") & "<br><br>" & Worksheets("E-mail Sheet").Range("B12") _
        & Worksheets("E-mail Sheet").Range("C12") & "<br><br>" & Worksheets("E-mail Sheet").Range("B13") _
        & Worksheets("E-mail Sheet").Range("C13") & "<br><br>" & Worksheets("E-mail Sheet").Range("B14") _
        & Worksheets("E-mail Sheet").Range("C14") & "<br><br>" & Worksheets("E-mail Sheet").Range("B15") _
        & Worksheets("E-mail Sheet").Range("C15") & "<br><br>" & Worksheets("E-mail Sheet").Range("B16") _
        & Worksheets("E-mail Sheet").Range("C16") & "<br><br>" & Worksheets("E-mail Sheet").Range("B17") _
        & Worksheets("E-mail Sheet").Range("C17") & "<br><br>" & "If possible please provide us this information by " & Worksheets("E-mail Sheet").Range("A2") _
        & "<br><br>" & "If you have any questions please contact " & Worksheets("E-mail Sheet").Range("A19") & "at " & Worksheets("E-mail Sheet").Range("C19") _
        & "<br><br>" & "Sincerely," & "<br><br>" & signature
        .display
        .SendUsingAccount = OutApp.Session.Accounts.Item(2)

    
    End With
    On Error GoTo 0

    Set OutMail = Nothing
    Set OutApp = Nothing
End Sub