For P-touch Editor 5.2:

Update your P-touch Editor to the latest version (5.2.020 or higher).

For P-touch Editor 5.1:

Do the following:

If you cannot open any files from [Open] - [OneDrive]:

1. Start P-touch Editor and click [Open] - [Computer].
2. Select [OneDrive] from [Look in] and choose the file you want to open.

If you cannot save any files from [File] - [Save to Web]:

1. Click [File] -  [Save] or [Save as].
2. Click [OneDrive], and then click the [Save] button.