When I try and run the Win 10 Anniversary upgrade (Windows10Upgrade28084.exe) I am informed that I do not have the 20 GBytes of free space on the C: drive required to proceed and the option to use an external drive is not presented:
As my laptop has only 90 Gbytes of available storage, with only 4 Gbytes currently free, obtaining 20 Gybtes free space by moving temporarily moving folders to an external drive is difficult.
Viewing the partitions with AOMEI Partition assistant I see that the Restore partition uses 20 GBytes of which 9.43 GBytes is free:
Is it possible to copy this partition to an external drive, delete it, expand the OS partition by 20 GBytes, run the Windows 10 Update, reduce the OS partition size by 20 Gbytes and then copy the Restore partition back (using AOMEI Partition Manager Standard)? I fear that the upgrade may require the Restore partition to be present in order to run OK.