Hi Nikos Sotiriadis,
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
Based on the information provided, it appears that your virtual machine is currently unavailable due to unexpected system reboots or shutdowns without following a proper shutdown process. Event ID 41 typically occurs when the system crashes or experiences sudden power loss, leading to a restart without the operating system shutting down correctly.
Event ID 41 may not be recorded, or the bug check code might be zero, which could indicate a power supply issue. If the computer's power is interrupted, it may shut down without generating a Stop error. In such cases, the Stop error may not complete writing the error codes to disk.
Consequently, when the computer restarts, Event ID 41 may not be logged, or the bug check code may be zero. For portable computers, this could be due to a removed or fully drained battery. For desktop computers, it could be caused by being unplugged or experiencing a power outage. Additionally, the power supply unit may be underpowered or faulty.
Please find the below document for more information:
Advanced troubleshooting for Event ID 41: "The system has rebooted without cleanly shutting down first"
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