You'll need WinZIP or PKUnzip to unpack most of the downloads. Most downloads contain .doc or .txt files, often called "readme.txt", read these! They contain valuable information about what you downloaded and how you should install it. The Emperor's Hammer missions all come with premade battle and pilot files which saves you the bother of editting them. In that case you can just overwrite the exsisting files, but do read the notes.

Note: The Tactical Manual has all the data you need for Emperor's Hammer use.

1. Go to your X-Wing Alliance directory. It is probably located in your Program Files directory. In there find a directory called Missions. Here are your missions located.

2. Find a mission that you have completed and rename it. For example, if you want to replace 1B2M1G.tie, rename it to 1B2M1Gbackup.tie. The mission is ready to fly. If the mission doesn't show up, check to see if you renamed it correctly.

3. Copy the new mission to the Missions directory and rename it to the name of original mission In this case, you would rename it to 1B2M1G.tie.

4. To restore the old mission, rename the new mission to something else or move it to another directory. Then rename the old mission back to its orignal name (1B2M1G.tie).

to Add new missions:

Very often custom-missions come with their own Custom Pilot files. By using these you get access to the custom-mission you have installed. Just place the pilot file in the X-Wing Alliance folder and the mission in the mission folder, then select the new pilot before you enter X-Wing Alliance.
If the mission you downloaded doesn't come with it's own pilot file and you don't want to overwrite your exsisting missions - you can will have to edit the Mission.lst file.

1. When you open the Mission.lst file in your Missions folder you'll notice that the layout is like this:

//
!BATTLE_2_HEADER![Battle 2: Secret Weapons of the Empire]
//
16
* 1B2M1G.tie
!MISSION_16_DESC!Flight Staff Transfer

I'll try to explain the format used:

- between the first // and the second // there is the title of your operation/battle. !BATTLE_2_HEADER! says what battle the title is from, in this case 2. Thats about the only thing you can safely edit in this part. The title has to be inside a [ and a ] to work but you can edit anything between those without a problem.
- then comes the number of the mission (in this case the "16").  The highest number in Mission is 58. This means that the missions you add have higher numbers. If a mission has already a number assigned to it (in the .txt or in delivered .lst file) preferably do not change this number.
- the mission file name, started off with a * and ends in .tie:. If the mission is in a subdir, that subdir needs to be there too.
- the mission title, this is what players will see inside the game. !MISSION_16_DESC! says what battle the title is from, in this case 16. Thats about the only thing you can safely edit in this part. The title has to be directly after that to work but you can edit anything after the second !.

2. You now add your new mission at the end of the .lst file, using a new number, or the number already asssigned to it by the mission's creator (unless already in use). Make sure that numbers are in numerical order. You are not required to put a mission in a new battle, but it does make it more easily understandable.

3. If you want to remove or disable your added missions, replace your new .lst file with that off your CD, or remove them from the .lst file manually.

Replacing Missions:
When you install a mission by overwriting, you will hear the old mission's briefing voices when watching the new mission's briefing.

AlliED: I you have AlliED and you know how to use it, you can also install missions using that program by clicking on the .lst button at the top of the main window. Here you can type in a mission description and click the Add button to add the mission.

Pilotfiles: I you have a program like XWAPiloteer and you know how to use it, you can also install missions using that program by creating a new pilot and then editting that pilot to have as next mission the mission you wish to play.

. TXT files: If your battle contains .TXT files like Shiplist.txt or Email.txt, backup the original files (Shiplist.txt is located in your main XWA folder, Email.txt in your Missions folder), and then overwrite them.

Unzipping: Do NOT just unzip any downloaded missions straight into your game directories. Always use an empty "Temp" directory.

Back Ups: all your original files are backed up on your CD - don't worry, it's easy to repair anything.