Nessma Diab 

I wonder if the way to address this is through the calendar type in your windows settings?  Trados Studio most likely takes these settings from windows as I don't believe we have options for the calendar type in Trados Studio:

Thank you for your assistance, Paul. Unfortunately, this solution did not resolve the issue. I changed my region and regional format settings, set the calendar to Gregorian as indicated in the first 2 screenshots, and even restarted my computer. However, not only did this fail to correct the date conversion, but it also created further inconsistencies: Trados retained the Gregorian year and day while converting only the month to Hijri as shown in Screenshot 3, resulting in an incorrect date display (e.g., a nonexistent year 2026 in the Hijri calendar).

Screenshot 1

Screenshot 2

Screenshot 3

Thank you for your assistance, Paul. Unfortunately, this solution did not resolve the issue. I changed my region and regional format settings, set the calendar to Gregorian as indicated in the first 2 screenshots, and even restarted my computer. However, not only did this fail to correct the date conversion, but it also created further inconsistencies: Trados retained the Gregorian year and day while converting only the month to Hijri as shown in Screenshot 3, resulting in an incorrect date display (e.g., a nonexistent year 2026 in the Hijri calendar).

Screenshot 1

Screenshot 2

Screenshot 3