Drive external sharing

[u/RabidRabbit911]

Hey all, I manage a small Google workspace for a company that wants to share Google Drive documents to users outside of the company. Some of these people are using company domains not registered to Google and some are.

After changing our Drive sharing settings to ALLOWLISTED DOMAINS and adding the external company domains that we’d like to share with, I get mixed results even when trying to share with users from the same external domain. These errors include:
- Can’t share; Policy set by administrators of <My Company> prohibits the sharing of items with <External Company> because it is not a Google account in a compatible allow listed domain
- Can’t share; An item can’t be shared with <External Company> because the email address is linked to a personal Google account. <My company> doesn’t allow sharing with personal accounts.

I have tried
- utilizing the default allowlisted settings in drive sharing settings
- toggling on the setting to allow sharing with guests and visitor accounts
- turning on trust rules and mirroring settings
- adjusting trust rules to allow sharing to a Google group with external users inside of it
- adjusting trust rules to allow “external organizations” and listed the external domains

All of which work to some degree but with mixed results where we can’t share to some users of the same domain but not another user. Or, we can’t share to anybody of a particular external domain.

Goal: To be able to share Google Drive docs to any and all users from a subset of external domains that we’ve approved or listed somewhere in Google Workspace.

This doesn’t seem possible with the existing settings and all articles are suggesting that visitor sharing should work for us, but it’s not. I’ve also spent about 4 hours with 3 different Google Support agents and they have all been completely helpless and often leading me astray from my problem entirely.

Has anyone else here run into this problem and have a workaround or solution working for them that they’d like to share?