Schema Mismatch/Downgrade Warning

Sometimes, when launching OnePager or attempting to open a .TAM or .TAT file, you will receive a schema mismatch warning like this:

In older versions of OnePager, the message will look like this:

There are two reasons that this can happen:

More Likely: Opening a Newer File Format in an Older Version

This warning message usually means that you are attempting to use a file that was created in a more recent version of OnePager than what you currently have installed.

If you have ever tried to open a Word 2016 file in Word 2003, you probably received a similar message from Microsoft. OnePager works the same way, meaning that older versions of OnePager are not guaranteed to work with files created in newer versions.

There are two ways to address this:

1. Recommended: If eligible, you can upgrade to the latest version of OnePager, which will allow you to read all OnePager files, regardless of which version they came from.

2. If the file that you are trying to open was given to you by a colleague, you can ask them to down-save his or her file to an earlier format that your version of OnePager supports. This can be done by going to File > Save As and picking an earlier version of the OnePager file format (TAM for project views; TAT for templates).

Less Likely: Mixed Installation

This sometimes also happens when a newer version of OnePager is installed in your account only for your use, but an older version remains installed in another account on your computer (e.g. an administrator account) and is available for ALL users, or vice-versa.The fact that an older version is available to ALL users means that it's available to you, even though you've upgraded to the newer version for your own use. This creates a conflict between the two versions of OnePager in your account. Here's how to fix the issue:

1. Uninstall OnePager from your account
2. Uninstall OnePager from ALL other user accounts on your computer (admin account, etc.) You may need your helpdesk to do this if you don't have access to the other accounts on your computer.
3. Once both versions of OnePager have been uninstalled, please reinstall the new version. You can do this in your account ("For Just me") or can do it in an admin account for all users ("For Everyone").
4. Once this is complete, restart your computer. OnePager should reappear on your add-ins tab, and the warning about schemas not matching will go away.

If these simple steps do not work, you will need to follow our advanced instructions for removing side-by-side installations.

Last Updated: June 9, 2021