Could you please press Windows + E and confirm whether File Explorer opens? If nothing happens, press Ctrl + Shift + Esc to open Task Manager, locate Windows Explorer under Processes, right-click it, and select Restart, if available. This restarts the Windows desktop interface without restarting the computer. Also, could you clarify whether the File Explorer icon has simply disappeared from your taskbar or whether the application no longer opens at all?
Regarding your Samsung T7, please connect it to your computer and press Windows + X > Disk Management. Check whether the external SSD appears in the disk list, even if it is missing from File Explorer. If the drive appears with a healthy partition but without a drive letter, Windows may simply have lost its previous drive-letter assignment.
Please do not initialize, format, delete partitions, or make other changes to the SSD, especially if it contains important files. If it does not appear in Disk Management, try a different USB port and check whether Windows detects the device in Device Manager. Since the problem started after a Windows update, please also check Settings > Windows Update > Update history and share the date and KB number of the most recent update.