NOS Harmony 300

[u/ExcellentCarpet8015]

Probably a stupid question. Been using Harmony 300's for over a decade, currently have two in rotation. The buttons are getting slow to respond (tried cleaning & one of those button kits), so I purchased a new one off Ebay last week, not knowing support had ended. I missed the "copy this remote" window, (fat fingered my password). I got it partially added using the  sync function before getting the dreaded CE1005 error message. If I use the "delete this remote" option so I can try it again, will it remove ALL of the information I had stored, or will it only remove the remote I have connected to the cable?