For access on the PC, I suggest you have a secure password for PC, and if shared with other to have separate profiles for each user, plus a primary password on Thunderbird, and two-step authentication online. That provides some degree of safety, but does NOT # provide reports on attempted activity to account (although a keystroke utility on PC may offer some information) # protect you from someone hacking the windows password (there is freeware that does that easily) # protect your account from someone browsing existing messages on the disk