It's just stage fright.
Write somewhere else.
Write while you're doing something else (watching TV, reading, walking ---NOT driving ;-) )
Write using a pen and paper.
Don't write, talk into a tape recorder.
Make word lists, go and take a break, then come back and write. (You can use some of the words, or not.)
Write about the problem. For example: "I want to write an article about this computer program. I want to mention these features___" etc
Write first thing in the morning. This seems to make it easier to write a lot for the rest of the day.
Hope this helps.
Cheers
Angela
Digital-e --- Info to go