Okay I'm going to try the 2nd method, pls tell me a method to backup my sql and then again importing the modified one...and also where to import the modified mysql... Sorry I'm new to all this...
Go to your cPanel. Click on phpMyAdmin under Databases.
In the sidebar, find the database name for your forum.
Click on Export on the top tabs.
Scroll down to Save as File. Make sure its checked. Leave all other settings as it is. Click 'Go' to save the sql file. Afterwards, save another copy just in case.
Open the sql file with a text editor like Notepad++. Find and Replace all instances of s40world.x10hosting.com with s40tech.net. Be careful not to include any spaces at all. Do not use a word processor.
Save the file (.sql).
Go back to phpMyAdmin.
On the Structure tab, select all tables and click the X to drop it. Make sure you have an original backup in addition to the newly edited copy. Here, you are deleting all database tables.
Go to Import tab and upload your newly edited sql file. Leave the other settings as is and click 'Go'.