Task SCheduler shows pcalua.exe with invalid drive

In my task scheduler I have four tasks listed with drive letters that do not exist. Here is one example:

C:\Windows\system32\pcalua.exe -a "E:\Users\Public\Downloads\Programs Hardware\nVidia\nVidia nForce 7 series 780a SLI\64 bit\Drivers\15.49_nforce_winvista_win7_64bit_international_whql.exe" -d "E:\Users\Public\Downloads\Programs Hardware\nVidia\nVidia nForce 7 series 780a SLI\64 bit\Drivers"

I know that pcalua is the program compatability agent. From googling, I haven't been able to discover why these 4 tasks would have drive letters that do not exist - and have never existed. Additionally, this one example appears to be with a driver installation. It is the right driver for my system, but I know better than to install drivers using compatibility settings. I am not the only user of the system, but I am the only administrator.

Installed drives:
drive A: floppy
drive B: (unused)
drive C: Harddrive
drive D: DVD-ROM
that's all that's physically installed. No hardware in (or attached to) the system has changed. There have been no drives mapped and then disconnected or virtual machines setup.

This leaves me with two questions I am trying to get answered:
1. Why are these entries here like this?
2. Can they be safely removed?

Hello and welcome to the forum.

First can you give us more info about your system...

1. Manufacture name....
2. Model number....
3. laptop or desktop...
4. 32 bit or 64 bit...

Plus if you have not done so I would recommend that you run a full updated virus scan using your anit-virus...

Next if you don't have then download and run a full scan using malwarebytes here is there link, use the free version...

Malwarebytes : Free anti-malware, anti-virus and spyware removal download

Please report back on the findings of both with your next post...