My Design Browser and Structure Window pane disappeared. How can I get those back?
You may try two things to resolve this issue:
Try moving your mouse to the left side as much as possible and see if the cursor changes into bi-directional arrow. If it does, drag the border to the right. The Design Browser was possibly collapsed to the left. In this case you may be able to drag it back.
If the step above doesn’t help, please do the following:
Execute program in Aldec install folder /BIN/prefman.exe
Use "Set Defaults" to reset current user preferences