Woah, I haven’t used M1 since 2017 (I think). And the last upgrade I did was in 2016.
If I recall correctly, I never used the Magento Connect Manager because it seemed totally broken.
Instead I upgraded using the patches that you can download from Magento. If you go to:
- Magento Tech Resources
- Select Release Archive tab
- Scroll down to the heading Magento Open Source Patches - 1.x (about half way down)
- Take note of the Patch Installation Instructions (I’ve copied below)
- Scroll down to the heading ver 1.9.x (about 2/3 way down)
- Download the Update/Patch you want to apply
That’s as far as I can take you. I can’t remember if you have to apply all of the other updates first or not. I’m sure it’ll say somewhere.
Patch Installation (Ref: Magento Tech Resources)
Please upload the patch into your Magento root directory and run the appropriate SSH command:
For patch files with the file extension .sh:
Example: sh PATCH_SUPEE-1868_CE_126.96.36.199_v1.sh
For patch files with the file extension .patch:
patch –p0 < patch_file_name.patch
Once that is done, refresh the cache in the Admin under “System > Cache Management” so that the changes will be reflected. We highly recommend you test all patches in a test environment before taking them live.
For further instructions, see: Installing a Patch for Community Edition
Oh, and it goes without saying stuff like backups and testing etc before deployment…