Hopefully, this post will help the ExcelForum Tech Staff reduce the number of Securi messages. When I attempted to 'Go Advanced' when editing a Private Message, the line in red below was the cause of a Securi SQL injection was detected and blocked message.

I know that line was the cause, because when I removed the line from the PM, the Securi message went away. When I put the line back in the PM, the Securi message returned

Private Sub txtAcres_KeyPress(ByVal KeyAscii As MSForms.ReturnInteger)
 If Chr(KeyAscii) Like "[0-9]" = True Or KeyAscii = 97 Then
 Else
    Beep
    MsgBox "txtAcres_KeyPress(): Only numeric values to be used!"
  End If
End Sub

Excerpt from Securi message:
What is going on?
You are not allowed to access the requested page. If you are the site owner, please open a ticket in our support page if you think it was caused by an error: https://support.sucuri.net. If you are not the owner of the web site, you can contact us at soc@sucuri.net. Also make sure to include the block details (displayed below), so we can better troubleshoot the error.
Block details

    Your IP: 96.234.66.73
    URL: www.excelforum.com/private.php?do=insertpm&pmid=206852
    Your Browser: Mozilla/5.0 (Windows NT 6.0; rv:38.0) Gecko/20100101 Firefox/38.0
    Block ID: SQLi71
    Block reason: SQL injection was detected and blocked.
    Time: Mon, 08 Jun 2015 15:11:07 -0400
    Server ID: cp447
Lewis