I get an error message when calling help for a command, what is wrong? 

You have probably not yet installed the HTML HELP. When you install GuiXT (either after downloading it from our website or by installing the version delivered by SAP) you do not install the help files automatically. You can download the .chm files from the download page of our website. Copy the files into your SAP GUI directory. For SAP GUI 4.6D this is in most cases  C:\Program files\sappc\sapgui.  For SAP GUI 6.20 it is C:\Program files\SAP\frontend\sapgui. Please note that the language of the help will depend on the language used for the logon (English/German/French). So, for example, if you have logged on in English, the English version of the help has to be installed.