We have just concluded testing a few scenarios for workarounds regarding the Basic Authentication and TLS1.0/1.1 deprecation and have published a detailed article for our customers. Thought I'd share this here, as some here might find it useful as well.
We have included information on using SMTP2GO, SendGrid, and Office365 Relay, of course, with the first recommendation being to upgrade to a supported version of Sage.
While we couldn't necessarily mimic exactly what Microsoft will be doing on October 1st, we have gone through some rigorous tests by altering certain settings in Office 365 tenants, like turning on/off security defaults on the domain and other controls that would enable/disable Basic Authentication and observed the behavior in all scenarios.
The recommendations in the below KB have been tested successfully with Basic Authentication turned off.
https://support.gotomyerp.com/portal/en/kb/articles/office-365-basic-authentication-deprecation-and-emailing-from-hosted-applicationsOne additional question we were trying to answer is whether the legacy-smtp.office365.com will still work as per this
KB and this
article. We found that while the legacy-smtp option will still be possible, it will only allow the tenant to revert back to using TLS 1.0/1.1 at their own risk but does
not allow for Basic Authentication. So this will
not be a viable option for a workaround. (We are not 100% sure of this, but based on our testing so far, we think that this is the case)
Hope you find this useful. If anyone has any additional useful information, I'd be happy to take it to our team to update this KB, if you would find it useful as a general resource for these workarounds.
UPDATE (08/30/2022): We had a client with Sage 100 2021 Premium PU1, and they were able to configure OAuth successfully (without installing PU4).
Also, we have amended the article the KB article with the following. we're not sure if this was specific to this client. But in case anyone faces the issue, try this:

In addition, it appears that (at least on Server 2016), the OAuth process from within Sage (with PU1) is spawning Internet Explorer, which will work ok, but make sure that you have TLS1.2 enabled in the Advanced Settings in Internet Options, or the redirect will result what looks to be a DNS failure with a "This page can't be reached" message.
Cheers,
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George Khairallah
CTO | gotomyerp, LLC
george.k@gotomyerp.com |
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