No login screen on startup, works after logging in and logging out again [closed]

Question

I installed Ubuntu on a client's computer. At first - no issue, but after some updates and installs (including burg, which was not the problem as the problem remained after removing it, I could not get lightdm to load correctly, until I switched to upstart.

Is this a known problem with a known fix?

New Details:

• The problem seems to go away once I log into a desktop and log out. The issue seems to be, however, that I'm unable to log out from Unity (I have to double check this), but I'm able to log out from KDE.
• Switching between TTYs is impossible once logged in, however (not tested on KDE yet, I will update with more information as I go).
• A cursor is visible on boot, but the touchpad is disabled, and has to be manually enabled after booting up.
• The problem is also occurring when using upstart, though this was not the case originally.
• The system in question uses intel graphics (I will update the question with precise specs later). There is no graphics card so it's not using Hybrid graphics.
• It is possible to log in from the blank lightdm screen because apparently despite the login screen not being rendered, it is working just fine (just type the password press enter and you're in.
• To reiterate, you can switch to TTYs until you're logged in (at least this is the case with Unity). Once logged in, as I mentioned earlier, this is no longer possible.

Second Update:

• I purged Lightdm.
• I've switched the system to SDDM for the time being.
• I'm now waiting for Lightdm to re-install (connection is being rather slow these days).
• Once Lightdm is reinstalled I will try changing the wallpaper (one suggestion I received) or trying another greeter.
• I did search the web for info but came up dry on this precise issue though I did find similar issues.

System Information:

Acer Aspire E1-431-2867:

• 2GB of RAM
• Intel Celeron B820 (1.7Ghz, 2MB L3 cache)
• Intel HD Graphics
• The rest... irrelevant and too long to list ;)

I will leave the question open for a little in case someone can find an answer (if someone does, then I'll still give the bounty I was going to).

At the moment however, I'm out of time and have decided to switch to SDDM so I can return the system to the owner.