Issue:
When AutoCAD Electrical is booted, a fatal error appears: "Fatal Error: Unable to connect to the Project Database Service". followed by "FATAL ERROR: unhandled e0434352h Exception at f4e1a388h"

Causes:
- Specific security update (KB4484127 or other) for Microsoft Office 2010 (and newer)
- The project database (MDB) file is corrupt and needs to be deleted (See * item in the Solution section)
Solution:
- Turn off All Microsoft Office programs as well as all Autodesk programs ( including Autodesk desktop app).
- From the Control Panel, Add/Remove Programs, click on the View Installed Updates on the left pane.
- Uninstall a Microsoft update named: KB4484127 (Usually under the category: Microsoft Access database engine 2010).
- Install the more recent Office update available here.
- Start AutoCAD Electrical again to check whether it works.
- If the problem continues, proceed with these additional steps:
- Make sure that you have access to the installation package of AutoCAD Electrical. ( If not present, download its installation package from your Autodesk account. manage.autodesk.com)
- Turn off All Microsoft Office programs as well as all Autodesk programs ( including Autodesk desktop app).
- From the Control Panel, Add/Remove Programs, under the main program uninstall windows, uninstall the product called: Microsoft Access Database Engine 2010.
- Reboot the computer.
- Navigate to the AutoCAD Electrical installation folder (by default under C:\Autodesk).
- Under the AutoCAD Electrical installation folder, navigate to the directory (<AutoCAD_Electrical_20xx...Win_64bit_dlm>\3rdParty\x64\AceDataEngine\) and install the application named AceRedist.msi.
After the installation is finished, run AutoCAD Electrical. It should be working now.
C:\users\<username>\AppData\Roaming\Autodesk\AutoCAD Electrical 20xx\Rxx.x\enu\Support\User (where the Xs denote the Electrical version).
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