Start here: most problems trace to a Windows, Office, or licensing-service change, each with a step-by-step fix below.
An April 2025 (and later) Microsoft 365 update disables ActiveX components, including the TChart plotting control.
Re-enable it in Access: Options → Trust Center → Trust Center Settings → “Prompt me before enabling all controls with minimal restrictions” → OK, then restart.
CETIS relies on the Windows Management Instrumentation (WMI) service to verify the machine; if WMI is disabled, login fails.
Re-enable it: run services.msc, set Windows Management Instrumentation to Automatic, start the service, and restart.
Confirm your administrator allows Trusted Locations for the CETIS directory and that Windows Defender isn’t blocking QlmLicenseWizard.exe.
A long-standing Microsoft LAN bug (introduced November 2018) can corrupt Access databases in shared environments.
Consult your IT staff; CETIS already uses UNC network addressing for linked tables to reduce the risk.
Legacy issues (Windows XP/Vista/7, Access 2007, graphs32.ocx, workgroup .mdw) are archived; contact support for legacy guidance.
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