If you tried to access https://ppms.ist.ac.at/ and only got the following result:
you are probably running an ad blocker in your browser.
Even though it is highly recommended to run one, it can also block legitimate pages. One blocker IT can suggest is: uBlock Origin, which is available for all major browsers.
To access PPMS, just disable your ad blocker on this page, if you are using uBlock origin, you would press the blue on/off button:
After a reload, the page loads.