I've run into an issue with an O365 SharePoint site created in 2018 where links shared with "anyone" and set to never expire appear to be expiring. I have checked our global sharing settings, and it is set to allow external sharing and the default 30 day expiry window has been disabled to allow the links to never expire. I've also checked the specific sharing settings on the site itself and once again, it is set to allow sharing with anyone and for the links to never expire. However, when attempting to access these links from computers that are not signed into any MS/O365 accounts associated with my tenant, I either receive and "Access Denied" error or it takes me to the generic O365 login page. Has anyone else seen this? Is there a setting somewhere that perhaps I'm missing? Thanks.
To be clear:
Global SharePoint sharing settings are set to the most permissive, "Anyone". File and Folder links are set to "Anyone with the link". The "These links must expire within this many days" checkbox is unchecked and there is no value in the number of days field. "Use short links for sharing files and folders" is checked.
Site specific settings are as follows: External sharing set to "Anyone". Default link type set to "Same as organization-level setting (Anyone with the link)". Expiration of Anyone links set to "Same as organization-level setting (Never)". Default link permission set to "Same as organization-level setting (View)".
Additionally, in the site collection settings the option "Limited-access user permission lockdown mode" is not enabled.
Any assistance is appreciated.

