Downgrading PT 2020.4 to 18.4

[Gamefreak]

Hope it's the right place for this post;
In 2016 I bought PT 12.5 (Perpetual Product) with a Standard Support Plan which expired 08-11-20. Accidetally I've upgradedmy PT 12 to 2020.4, but the last version covered by my Support Plan was 18.4.
Immediately I have bought a new Annual Subscription, but it was already too late: "PT cannot be launched ("Subscription expired...") and the new subscription cannot be downloaded.
I tried to "overwrite" the PT 2020.4-version on my pc with PT 18.4 which didn't work, and neither did overwriting it with PT 12.5.
Every time the installation was interrupted with the message "Error 2753: the file "mmerefresh.exe is not marked for installation".
Do I have to completely remove PT 2020.4 from my pc and reinstall my first Version (PT 12.5) or is there any other way?
Thank you

My System: Win 8.1. Pro, Intel i7-4790, 3,6 GHz, 32 GB Ram, Samsung SSD; Steinberg UR 242

[JFreak]

Hi, welcome to the community.

Compatibility info here.

[Gamefreak]

Okay, I've seen: wrong OS for the PT-Version...
But is there any way back to PT 12.5 or 18.4?

[JFreak]

Just install the version you want to be using. Your license has a RELEASE LIMIT date that determines the latest version you can use. Earlier are okay. If you have problems it is very much recommended to do a clean install of OS and start over.

[64GTOBOY]

To answer your question, yes, a clean install will probably be required unless you can do a system restore and or have a back up/clone of your system drive

[Gamefreak]

Thank you for your quick replies
Unfortunately I have no backup of my system; I would not like to change my OS because it ran stable for four years.
Now I will run the uninstaller and remove Pro Tools from my system and try a clean installation of PT 18.4 which is the last version I am allowed to load.

[JFreak]

Clean install means starting over with OS


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[Gamefreak]

It is done!!

I've deinstalled the current PT-Version, then reinstalled PT 12.5 (didn't work...) and then upgraded to PT 18.4
...it works!

Thank you for your patience

[JFreak]

Good to know you got it going


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