You may see certain shapes like a 'bullseye' or a large cross mark blocking the design workspace. These are visual symptoms of an incompatible graphics card. Please check whether your system meets the minimum recommended graphic requirements using: http://files.spaceclaim.com/DxDiagTool.exe
Try looking for a graphics card driver update through the 'Windows Device Manager' on your PC. After installing it (if available), restart your PC and launch DS Mechanical again.
If your graphics card requirements are met but you still see the 'Graphics is not available' message, try deleting contents of this folder and then starting DSM: C:\Users\"Your Windows username"\AppData\Local\SpaceClaim\
The 'AppData' directory may be hidden by default on some computers. To view it, do a Windows search for 'Folder options' or 'File explorer options' and then go to 'view' tab-> select 'show hidden files & folders'.
'Failed to create Direct3D11':
If you see the above error message, then switch the renderer to OpenGL for resuming your work quickly (this option is available in DSM v4.0 & newer, see next section on how).
Please also check that DirectX11 is updated for your version of Windows: https://support.microsoft.com/en-gb/help/179113/how-to-install-the-latest-version-of-directx
For Windows 7 Service Pack 1 users encountering "Failed to create Direct3D11", please download and install this platform update: https://www.microsoft.com/en-us/download/details.aspx?id=36805
If none of the above work, there may be a corruption with the Windows DirectX driver files. Run the SFC tool from Microsoft to repair them: https://support.microsoft.com/en-us/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system
If you see pixelated designs like:
Try reducing the software window size slightly from your normal full screen view. It should fix the design render.
In DSM v4.0 and newer:
Once you have checked that the graphics card requirements are met, go into File -> DesignSpark options -> Advanced -> Renderer and switch to OpenGL from Direct3D. Restart DSM again after changing this.
If you have a computer with switchable graphics, assign a different graphic card to be used with DSM (switch from one which is causing the grey box to appear).