Grapher: "Document could not be opened"

If it works in the Safe Mode, try running this program when booted normally and then copy and paste the output in a reply. The program was created by Etresoft, a frequent contributor. Please use copy and paste as screen shots can be hard to read. Click “Share Report” button in the toolbar, select “Copy to Clipboard” and then paste into a reply. This will show what is running on your computer. No personal information is shown. You can run the report for free at least once, but if you run it several times, at some point it will ask you to pay a license fee.

Etrecheck – System Information

• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions
• Prevents startup items and login items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files

All boxes in documents in the above screen shot are to be checked mainly desktop and documents folders .

Followed the method .

• Create a new graph: Choose File > New, then choose the type of graph you want to create.
• Add your own equation: Click the Add button in the lower-left corner of the Grapher window, then choose New Equation to create your own equation.
• Add an equation from a template: Click the Add button in the lower-left corner of the Grapher window, then choose New Equation From Template to add parametric equations, curves equations, vector field equations, or series from templates.
• Edit an equation: Select an equation in the equations list, then update the equation in the edit field above the graph.
• Add an element to an equation: Click the Add Elements pop-up menu to the right of the equation field, then choose Show Equation Palette. You use the Equation Palette to add standard elements (exponentiation, roots, and absolute values), operators, Greek letters, and symbols to your equations.
• Delete an equation: Select the equation in the equations list, then press the Delete key.

You have to save in iCloud Drive in finder , right click on the untitled folder and open with grapher.app( default ) or even you double click on it , and it opens .

Open system preferences > iCloud > iCloud Drive > click on options > select documents make sure the the box of grab.app is checked .