all thumbnails of drawing options are missing in my revit architecture, but all explaination texts still show when put mouse on it. It shows as the attachment.
I have already reinstalled software, cleaning all existing files including metric library and install it again, but still do not show up.
Also, some properties dialog thumbnail previews are also missing. The attachment "property" shows the mullion, not from inserted families, no property information is shown and when go into edit type, the preview window is empty. Revit on my university lab's computer has these previews, so I don't know what is wrong with mine.

need help, thanks