Files shared with Anyone sometimes prompt users to request acccess to the file

Day270  That is the problem.  One drive has the option for the owner of a folder to send permission or obtain a link that allows anyone with the link to access the folder WITHOUT having to log into One Drive.
What is happening is sometimes the popup you mention comes up.  It's presumably due to MS OR the browser being used, 'assuming' the person attempting to access the folder is required to log in for folder access. 
The link is SUPPOSED to specifically allow the user access WITHOUT a login.
My personal belief is if a browser used to attempt access has cookies or a cache file that triggers a login request, then the link is not configured correctly. My personal experience is to use a 'virgin' browser and the problem seems to go away.

Raul_B_    I am amazed that this problem still exists after years and numerous complaints.   This does not seem as if it should be a very difficult issue to scope out by Microsoft and apply a fix.  OneDrive has been around a long time.

I started using OneDrive when Amazon gave up its AmazonDrive as of EOY.    This inconsistent bug about asking people to sign in, when it's an "Anyone with Link can View" link-share is frustrating beyond belief.   

At this point I would recommend OneDrive to no one.   I will be researching other products, as this product (and its support group) doesn't seem to cut it.

Wondering if anyone has opened a case with Microsoft recently, and what the official response is? 

nickf23 these steps don't work in my personal OneDrive.

• "Return to classic OneDrive" isn't an option -- I see only "Premium OneDrive", "451GB used", and "Get the OneDrive apps".
• If I theorize that maybe I'm already in Classic and proceed to the settings gear, I don't see "Site settings", nor do I see "People and Groups" on any subsequent page.  My gear options are "Options", "Upgrade", and "English (United States)".

In my nonprofit org, I am able to follow the Sharepoint steps.  However there are two problems:

• You have a typo in the URLs.  Should be "_layouts" not "_layout".
• Upon reaching this page, I do not see the troublesome user account.  For example, given my recent experience of being asked to (re-)authenticate via personal identity, I'd expect to see email address removed for privacy reasons listed as an erroneous guest account here.  But it's not there.  Nor do I see the work/school accounts of end users who've complained in the past. 
  
  I do see my nonprofit identity (email address removed for privacy reasons) in the list, but I'm obviously not going to delete that -- I'm the only site admin!

I have consistently experienced this problem for many years, against both personal OneDrive and ODFB (Sharepoint) backends.  The "bad" recipient is always someone with a Microsoft identity (e.g. Hotmail or a work/school account).  Sometimes it's me -- literally unable to access a "share with anyone" link that I created just moments ago, unless I fish out my phone and re-enter my 2FA.

Fully anonymous users don't seem to be affected.

Needless to say this is a terrible UX.  I run a tiny nonprofit (<5 users), so virtually everyone who receives a OneDrive link is a so-called "guest" in MS terminology.  Most of these collaborators, vendors, volunteers, etc have no connection to MS and thus do fine.  But those that do -- because it's required for their work, school, or Xbox -- get the worst experience of all, rather than benefiting from familiarity with the MS ecosystem.  It's particularly baffling for power users with decent tech skills and their own account @ my nonprofit, because they will (quite reasonably) try to type the password for my org -- the tenant from which the file is shared -- rather than the work/school account that their screen is actually prompting them for.

To put it bluntly for StephenRice and his fellow PMs: requiring extraneous auth turns your potentially strongest users into the loudest voices for abandoning MS tools.  As everyone reminds me (tech & nontech alike), GDocs simply does not have this issue.

SimBur2365 

I can appreciate your obvious superior knowledge on the inner workings of Microsoft's complex relationships.  I also understand that there complex relationships are very likely required for security and functional operation.

However your missive doesn't help the less that expert user understand how they can resolve the situation, as there are no specific, detailed, and clearly defined steps listed to resolve the issue.
With all due respect, I realize your statement might resolve it for an experienced software engineer, familiar with the inner workings of the global Microsoft system, but for the vast number of users who do not have that skill set, what you have written does not offer a concrete, workable solution.  
As an aside, it appears you assume most individuals reading these are well versed on the system as you are. To be blunt, we aren't. Also to be blunt, documentation for solutions needs to be in layman's language as much as possible, and needs to be tested against an untrained individual.  I see this VERY OFTEN in these types of forums, in which a solution is offered, and the author is so familiar with the systems that they inadvertently leave out key steps, which to them are second nature, but to the inexperienced user are NOT a typical option they would invoke.  For instance, many times when a change is completed, the window needs to be "Saved". Many end users may not be familiar with the particular window, and may not complete the last step, negating al the previous work.  I have found a series of step by step screen shots, with arrows or highlights of the critical operations to be accomplished in each step are helpful. 
Again, with all due respect, I have little doubt that your paragraph does address the root cause and the solution. But without the kind of documentation I mention above, it does little to help the inexperienced user solve the problems, AND CREATES FURTHER FRUSTRATION ON THEIR END. Creating one more small negative public relations impression for Microsoft. 

Lmarin1980I use Firefox as a browser. I also keep IE and Edge on my computer.  When I create a folder in One Drive and Share it with  a link, BECAUSE I have a hosted exchange account with MS, it appears as if any time I create a link, and attempt to use it myself, the browser references my MS account.  And therefore wants validation for a username and password.  IF I use a browser that is NOT associated to my MS account (from past use) such as Edge, then the link opens WITHOUT asking for log on credentials.
I have warned other users that I send links to, that they need to either have a browser that has NOT been infected with MS tracking cookies or other markers, then the link should open.  If they do not have that option, then they should clear their browser cache and cookies.  I have not had anyone tell me that process does NOT work.