Tekkit is a pack of mods (modifications) for the computer version of the game Minecraft. All the mods in it can be used together. You have to set up the Tekkit server first if you want to play this game with all mods AND your friends!
Step

Step 1. Download the Tekkit server software

Step 2. Extract the zip file to a directory on the desktop

Step 3. Run the "launch.bat" file

Step 4. If you get an error file, right click the " launch " file and select Edit

Step 5. Replace "Xmx3G -Xms2G" with "-Xmx512M -Xms512M"

Step 6. Run Hamachi if you STILL get the error message

Step 7. There are some numbers next to the power button
Copy the numbers.

Step 8. Open the "server.properties" file in the Tekkit Server directory

Step 9. Look for the value "server-IP= XXXXXXXXX"
Replace the row of numbers displayed with the number you copied from Hamachi.