Hi Hugo,
I’d like to confirm some information to narrow down this issue:
1. Are all folders under OneDrive for Business experiencing this issue? Does this issue happen in other libraries? Try creating a new folder, adding some files and testing if it works.
2. Access your OneDrive for Business library directly in browser using the current credential, open the folder and check if it works.
3. Does this issue occur on other SharePoint sites? Have you tried connecting using another account?
4. Try opening files on another computer, does it works?
5. Please get a capture regarding “you are redirected to my main page”. To insert a screenshot, please click on Use rich formatting and select the Insert Image icon.
Best Regards,
Vincent