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Hubble Space Telescope
Test for Communication Problems with APT

Please try these steps to test for and resolve communication problems with APT:

  1. Install and start APT
  2. Test access to documentation

    Click on the "Help" menu and select "Phase I Call for Proposals".

    1. If it worked you will see the Call for Proposals document pop up in a separate window. Go on to step 3.
    2. If it didn't work you will get a message like:
      Please check network status

      If you are in fact connected to the internet, please set the HTTP proxy:

      Go to the "Edit" menu (or "APT" menu on Mac), click on "Preferences", select the "Network" tab and enter your HTTP proxy host and port. (Your system manager should be able to supply you with these values. You may also be able to find them in the preferences for your web browser.)

      Quit APT and start it up again.

      Now try the test again. If you still can't connect there may be a problem with the proxy information you put in; please double check. If it still doesn't work, please send e-mail to

  3. Test access to investigator database

    Click on the "New Document" button and choose "New HST Proposal". Then click on the "New Co-I" button. Type in a name like "peter" and hit return.

    1. If it worked you will get a pop up that gives numerous people whose first or last name begins with "peter". Go on to step 4.
    2. If the connection to the server cannot be establish you will likely not be able to type into the Name Search box (and the word "Offline" will appear next to the Name Search box). Alternatively, if the connection was lost while you were typing into the Name Search box you might get a pop up message like:
      Unable to contact the STScI server

      If you are in fact connected to the internet then the server may actually down. But it is also possible that you need to go to "Edit" menu (or "APT" menu on Mac), click on "Preferences", select the "Network" tab and click on "Force HTTP".

      Quit APT and start it up again.

      Now try step 3 again. If it doesn't work please send us e-mail at

  4. Known problems

    When you have finished these steps, you should be set up to use APT without any communication problems.

    Note that if you have had to turn on "Force HTTP" the submission will be slower, but it should still work.

    There is one known bug with "Force HTTP": If your attachment is large (>5MB) you may get the incorrect message "Unable to contact STScI submission server". If this happens to you please submit with a dummy attachment and contact We will arrange to get your attachment via e-mail.