In order to be able to use SQL Native Connection Prvider instead of OLE DB you have to perform some additional actions.
Even if you are using a later version of Microsoft SQL server (for example SQL 2019) you must download and install the SQL 2012 Native client (also known as 'SQLNCLI11.1'):
1. Download the 64-bit Microsoft SQL 2012 Native client (sqlncli.msi)
2. Logon to the SQL application server
3. Double-click on the file: sqlncli.msi
4. Go to the DeskAlerts Server, open the folder c:\inetpub\wwwroot\DeskAlerts\admin
5. In the file functions.inc.asp find the string getconnection (2142 row in that case) and change provider to the SQLNCLI11
Then, restart the AppPool and it will allow you to use SQL Native Client connection.