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OST - Planroom Projects Issues

Views: 771 Last Updated: 02/14/2023 08:31 am 0 Rating/ Voters
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Cannot Launch/Download a Project


You try to launch a project by clicking a link on your planroom's site but On-Screen Takeoff (OST) doesn't open or the project is not created.


You have an existing project and the plans will not download from within On-Screen Takeoff.


Although there may be several reasons why this is happening, the most common reasons and resolutions are:

  • The planroom's Project file (OSX file) was not written to function correctly with On-Screen Takeoff. You can try to save the OSX file to your desktop and manually import it by following the instructions in the OST User Guide (see "Importing"). If that doesn't work, you will need to contact your planroom for assistance.
  • On-Screen Takeoff is not installed or not installed correctly on your computer. There should be an On-Screen Takeoff icon on your desktop - double-click it to launch OST. If OST launches correctly, make sure you have a database open (see the User Guide for help with opening and/or creating a database).
  • Your computer's Internet (Firewall) or Virus security is not allowing the download/import of the OSX file - please disable any Internet or Virus software briefly and try again. Contact your IT department for assistance.
  • The project is no longer valid. If you are accessing an existing Job but cannot download individual pages, the project may no longer be available on your planroom's site. Please contact your planroom for assistance after verifying your Internet connection is working.
  • The product is not configured properly, keep reading...

Downloaded Plans Are Not Being Saved

When you attempt to download images from a Planroom, On-Screen Takeoff appears to complete the download, however the images are not displayed and the files are actually not saved on your network.


If your Planroom Folder, under Tools > Options, is set to a network location that is not a mapped drive (assigned a letter), On-Screen Takeoff cannot create a project folder in which to store downloaded files.

On-Screen Takeoff will create the project, but cannot save the images because the folder structure cannot be created.


You must map the server location as a Network drive. To map a network drive, perform the following steps:

Consult the Help and Support applet provided with your version of Windows for specific information on mapping drives, the process is similar on most versions of Windows. If you need further assistance, contact your IT department or Network administrator.

  • Open My Computer by clicking Start > My Computer
  • On the Tools menu, click Map Network Drive
  • In Folder, type the server name of the computer you want (example: \\server) or click the Browse button to find the computer
  • Select the Drive letter you wish to use, verify Reconnect at logon is selected, and then click Finish

Once the network location is mapped, in On-Screen Takeoff click Tools > Options, click the Folders tab, and then enter the mapped location under Planroom Folder

Testing Planroom Projects


You need to test your On-Screen Takeoff installation to verify it can download Planroom projects.


On Center has a project you can download to test that your On-Screen Takeoff installation is working properly.

Click the link below to download a test OSX file.


Save this file to your desktop or another handy location.

Double-click the file - it should automatically open On-Screen Takeoff, create the Project, and load the "Planroom subtab" on the Image Tab.

See OST - 11.08 Downloading Plans from a Planroom or DFS for more help with using planroom project files.


  • If the project downloads and you see an image explaining that your installation is working correctly - please contact your Planroom directly for assistance. There are many reasons why Planroom projects stop working - usually, the Planroom has removed the project from their site, or you need to log into the Planroom site again.
  • If the project downloads and OST opens and imports the file but you do not see the image explaining that your installation is working correctly, OST cannot download the project images from the Web site. This is probably a firewall issue, you do not have sufficient rights to create a folder in the location specified in OST's Folder options, or the path to that Planroom folder is too long. Your IT person needs to assist you properly configuring OST's options.
  • If the project downloads but On-Screen Takeoff doesn't open, you probably need to re-install On-Screen Takeoff. Open the Windows Control Panel, uninstall On-Screen Takeoff, and then install it again - something may have interfered with the registry settings that allow OST to 'control' osx files.
  • If the project doesn't download, your firewall or virus scanner may be blocking it. You will need to resolve this with the help of your IT person.

When you are working in a downloaded project and PDFs (spec pages, for example) open in an external browser, this is not a problem with On-Screen Takeoff. The program is working as intended. Your Planroom has configured the project to open PDFs in an external browser. There is no setting in OST that can change that, you will want to contact your Planroom directly. You can download these PFDs, then manually add them on the Cover Sheet, see Related Articles for details.

PlanViewer Will Not Run Without Internet Connection

On-Screen Takeoff works fine when plugged into the Internet, however, when disconnected On-Screen Takeoff the program generates the following error message:

Can't authorize program, check internet connection or your authorization will expire soon

Database(s) become locked/read only and the application does not function correctly or may not launch at all.


There is an unused dongle driver installed on the machine interfering with On-Screen Takeoff.


Remove any Sentinel System Drivers from the affected machine.

This only affect unlicensed (On-Screen Takeoff PlanViewer) users.

Product documentation (user guides) describes functionality in the latest version of each major release and may not match the functionality in the version you are using. Please check the Product Information and Downloads pages by clicking one of the product buttons above.

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