as per below link not much option you got rather than checking the correct hotname etc...
-10709: Connection failed (<description>) (SAP Library - Basic Information)
-10709: Connection failed (<description>)
Explanation:
Connection to the database instance failed.
<description> contains the internal error message.
User Action:
- Check whether you entered the right connection data (name of the database instance, name of the computer).
- Check whether the database instance is ONLINE.
- If you want to establish a connection to a database instance on another computer, check whether the X server is running on the other computer.