SYMPTOM:
In Strategy Web using IIS, the Main.aspx page displays as a blank page when trying to access it, like shown below.

When viewing the page source, only the headers show, like below.

However, users are still able to access the Admin.aspx page correctly.
CAUSE:
The PageConfig.xml file has been corrupted or is missing.
ACTION:
Run a repair on Strategy Web to restore the Strategy Web installation files.