If you get one of these server errors, just reload the page until it loads properly. Please bear with us, as this is a problem with the Invision boards and isn't something I can fix.
If you're making a long important post, I'd advise you to copy the text to Notepad before posting so you can save it in case there's a server error when you go to post. You can copy text by clicking on your left mouse button and dragging the mouse over it, then press Ctrl+C at the same time. Go into Notepad and press Ctrl+V at the same time to paste it in. This will save you grief.