Drastic Steps Around Preflight Error!

At this point I guess I need to give up. It will maybe run 1 time out of 15 to 60 attempts. I have done everything suggested here. As for my version of Windows. It was the free upgrade. However I don't like upgrades so the day I did this I deleted my Windows 7 and then did the 3 hour refresh or whatever they call it.

I just have no idea. I even found a fresh installation of 10. I used it to install again using my serial. Thinking maybe something was corrupt.

I will mention I have a few virtual machines on this system. I removed it from my host and installed it on a fresh clone. The clone's properties was a windows 7 with the Win10 upgrade then deleted the Win7 and let Win10 completely erase Win10 and reinstalled. Same thing as with my host. The darn thing installed and worked perfect. But I had to put it back on this side of the machine. Same thing happened.

My thinking is it is something with my current installation but I cannot find anything. Went through the registry looking at most keys where things like to hide and it was clean. I run Malewarebytes Pro, Kaspersky Internet Security and once a week I go to Trend Micro online scan of Housecall. I also have Emsisoft Anti-Maleware. On one of the guest machines. I open up and I use McAfee Total Protection that is installed on it to scan the host.

With all of this nothing shows up every. I used a rootkit scanner as well. Still nothing. I pulled some dll and dat files that were on the guest machine that it worked on. Booted to from the disk and replaced them and it still won't work. I cannot come up with anything else. So I am about done with it.

I thought that the Acrobat Cleanup and Repair Tool was supposed to take care of all of this. And did you try repairing the installation clicking on HELP --->> "Repair Installation"?

If you've used the Acrobat Cleanup and Repair Tool , that also means that you were supposed to install a fresh and and fully updated to the latest version of Adobe Acrobat Pro DC in your machine.

Is this the recommended Adobe guidance that you've  followed and nothing at all was resolved?

If you didn't, Adobe recommends to use this tool: https://labs.adobe.com/downloads/acrobatcleaner.html

Also from the way you're describing the issue it looks like you were using an older version of MS Windows and upgraded to MS Windows 10 on top of the old Windows installation? (that's just another guess... I may be wrong). But if that is the case, be aware that some directory  structures might've change and Adobe Acrobat should've been uninstalled before the upgrade took place (then reinstall it on top of the newly installed operating system). 

However, regardless of the methods that you've attempted in the past with no avail, I would've try creating a new user profile , a fresh Windows user account and install Acrobat there afresh.

OR,

Enabling the hidden Administrative Account (better known as the "built-in administrator account"),  and boot into Safe Mode. Then log in with that Adminitrator Account and manually remove the hell out of every suspicious crap that you can (could've, should've, would've) lay your hands on  in that computer. 

For your convenience, before you reboot  into Safe Mode open up the command prompt as Administrator and type in :

net user administrator /active:yes

Then reboot and choose Safe Mode; log in using this built-in admin account. I have to stress that you only perform these type of manual software removal with the built-in Administrator account while in Safe Mode. This won't work if you're running MS Windows because a lot of services and applications are running in the background ieven if a program is not in use.

And here's a BONUS: if you're really that type of troubleshooting self-taught guy, then enable the legendary "GOD MODE" folder. See here how to: https://www.howtogeek.com/402458/enable-god-mode-in-windows-10/

But going back to what I was suggesting about creating the new user account, let's say that this soultion would've worked from the get-go, then you would've saved a lot of valuable time and frustrations instead of trying to do random-guessing and troubleshooting your operating system in the blind with no proper structure.

However, to answer your inquiry more appropriately the issue with "preflight.dll is missing or corrupt" doesn't necessarily mean that this essential file  is missing. This basically  means that in order for the the host  program(s) to load up properly, when it calls for that  dynamic link library, it doesn't find it in the directory (or windows folder) where it's supposed to be.

Here are a few ways that you can explore:

• update all the .Net redistributables
• update all Visual C++ redistributables
• use the DISM command and perform a system health restore to force the appropriate  registration of all DLL's in that system. Use this simple Micrtosoft guidance to achieve this method: https://support.microsoft.com/en-my/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system
• Manually registerring a DLL or OCX file : see this contribution that I offered in the Adobe XD support forums to work around  a similar DLL issue: https://community.adobe.com/t5/adobe-xd/troubleshooting-adobe-xd-crashes-white-screen-on-launch-on-windows-10/m-p/11253537?page=7#M32493 (it may work for some people, and it  is technical in nature; not everyone seem to experience a successful result) 
• If that link above is not enough for you then  see how it's done here: https://www.youtube.com/watch?v=KD5RVG7CKCA