Recently i've been working with the Harmonized World Soils Database(HWSD). I ran into some problems with getting it into ArcGIS but I have finally figured it out and i'm posting this so that anyone can use the dataset.
First step is to go to this website and download the files at this website.
After you have downloaded and unzipped these files open up arc catalog.
Follow these instructions for adding a OLE DB
(If you have 10.0 or 10.1 the instructions are the exact same.
After you have done that open up ArcMap.
Add the raster that was provided with the HWSD
If the dataset is unprojected run Define Projection (Data Management Tools/Projections and Transformations/Define Projection) and set it to World Geodetic Systm 1984.
After that run the Build Raster Attribute Table(Data Management Tools/Raster/Raster Properties/Build Raster Attribute Table) on the raster.
Right click on the raster in the table of contents and select Joins and Relates -> Join.
Keep the dropdown as Join attributes From a table.
For the second drop down(number 1.) Choose the field Value
for number 2, click the open folder on the right side and browse to your Database Connections.
Double Click the HWSD you added earlier and Add the table HWSD_Data
For number 3's dropdown select the field MU_GLOBAL
Keep the radio button selected for Keep all recrods
You can then click validate join, currently 1 row will not be joined but the rest work perfectly fine.
That's it, now you have the HWSD in ArcGIS with all the attributes populated.