Hi @Peggy F ,
Welcome to our forum!
The file C:\Users\user\AppData\Local\Outlook\email - Test.ost cannot be opened
In order to verify, what type of account are you using? Is it an Exchange/IMAP account?
What detailed version of Outlook are you using(File > Office Account > About Outlook)? Check the version and upgrade it to the latest.
Now it seems things work fine so my question is: Is what I've done okay?
Based on my search, .pst file is stored in C:\Users\Administrator\Documents\Outlook Files
According to my tests, these two are the same path, and I can't be sure because your copying the data file to the default path fixes your pst file.
This issue may also occur due to a corrupt Outlook profile, given this case, it recommended you delete your existing profile and create a new profile via Control pane > Mail > Show profiles > Add then re-add your account and see if the issue continues.
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