It seems the Factory Image has be removed. Factory image is designed to be available indefinitely as long as the "Dell PC Restore partition (DSR)" is not removed or the MBR (Master Boot Record) is not changed.
Please check in the "Disk Management Console" if the "Dell PC Restore partition (DSR)" is visible. This will be listed as a "Healthy (Unknown Partition)".
To access "Disk Management Console":
1. Press and hold the Windows Key on the keyboard and then press `R'.
2. In the Run Dialog Box type `diskmgmt.msc' and hit "Enter".
Do reply with results.
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