HP Microserver N54L XPEnology Upgrade (to DSM5.0-4493-update3)
Just upgraded both my N54L from previous XPEnology DSM4.2 to the current latest DSM5.0-4493-update3 
Been running the old XPEnology DSM4.2 never turn-off for more than 5 months now, so far so good both still kicking alive 
I have 2 other original Synology units (DS110j & DS213), been getting quite some updates from Synology past few months, the current latest DSM5.0-4493-upate3 seem settle down for few weeks without any further update, yet.
It's nice to see those XPEnology sifus out there continue to make the installation/upgrade process easier, they also managed to get the current latest DSM5 runs, so I guessed it's for me to upgrade both my N54L to DSM5 as well.
Basically I'm using resources from the following link, all credits & thanks to them, nice work
It's pretty straight forward and easier now, I just follow the steps ...
Download the following boot image, DSM & tools:
Get a new USB (or format it to FAT32), use the Win32DiskImager application to prepare the new DSM5 bootup USB
Use the new USB to boot-up N54L, select Install/Upgrade option
Boot until seeing the following "DiskStation login" status :
Then go back to PC, launch the Synology Assistance application & search, saw my N54L at "Migratable" status
Right-click it to Install
choose the DSM5-4493 pat file image, following the screen to complete the setup
Wait patiently, the N54L will re-boot few times, DO NOT touch anything until it's fully completed !
Upgraded from DSM4.2 straight to DSM5.0-4493, done !! 
!!
Next is to apply current latest Update3
Need to enable SSH login
Disable the auto-download update
Select the Manual Update, choose the Update3 pat image file, click OK 1 time then stop there !
PuTTY login to the N54L, must use "root" login ID, password is the admin password entered during DSM installation
Enter the following 2 command lines:
sed 's/flashupdateDeb/flashupdateDeb1/' /This email address is being protected from spambots. You need JavaScript enabled to view it. > /This email address is being protected from spambots. You need JavaScript enabled to view it.
mv /This email address is being protected from spambots. You need JavaScript enabled to view it. /This email address is being protected from spambots. You need JavaScript enabled to view it.
Then go back to DSM, click OK to continue
Wait patiently until the update process complete
Update done
Next, XPEnology + Plex media transcoding on HP DC7800 old PC
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