"?" character in MSSQL DB getting replaced with (capital A with grave accennt) when displayed by ASP script - sql-server

Question

I'm attempting to provide support for a legacy ASP/MSSQL web application - I wasn't involved in the development of the software (the company that built it no longer exists) & I'm not the admin of the server where it's hosted, I just manage the hosting for the owners of the site via a reseller account. I'm also not an ASP developer (more a PHP guy), and am not that familiar with it beyond the basics - updating DB connection strings after server migrations, etc.
The issue is that the site in question stores the content of individuals pages in an MSSQL database, and much of the content includes links. Almost all of the internal links on the site are format like "main.asp?123" (with "123" being the ID of a database row). The problem is, starting sometime in the last 8 months or so*, something caused the links in the DB content to show up as "main.aspÀ123" instead - in other words, the "?" character is being replaced by the "À" character (capital A with grave accent). Which, of course, breaks all of those links. Note that Stackoverflow won't allow me to include that character in the post title, because it seems to think that it indicates I'm posting in Spanish...?
(*unfortunately I don't know the timing beyond that, the site owners didn't know when the issue started occurring, so all I have to go by is an archive.org snapshot from last October, where it was working)
I attempted to manually change the "?" character in one of the relevant DB records to "?" (the HTML entity for the question mark), but that didn't make any difference. I also checked the character encoding of the HTML code used to display the content, but that doesn't seem to be the cause either - the same ASP files contain hard-coded links to some of the same pages (formatted exactly the same way), and those work correctly: the "?" doesn't get replaced.
I've also connected to the database directly with the MSSQL Management Studio Express application, but couldn't find any charset/character encoding options for either the database or the table.
And I've tried contacting the hosting provider, but they (M247 UK, in case anyone is curious) have been laughably unhelpful. The responses from them have been along the lines of "durrrrrr, we checked a totally different link that wasn't actually the one that you clearly described AND highlighted in a screenshot, and it works when we check the wrong link, so the problem must be resolved, right?" Suffice it to say, I wouldn't recommend them - used to be a customer of RedFox hosting, and the quality of customer has dropped off substantially since M247 bought them.
Any suggestions? If this were PHP/MySQL, I'd probably start by creating a small test script that did nothing but fetch one of the relevant records and display it's contents, to narrow down the issue - but I'm not familiar enough with ASP to do that here, at least not without a fair amount of googl'ing (and most of the info I can find is specific to ASP.net instead).
Edit: the thread suggested as a solution appears to be for character encoding issues when writing to MSSQL, not reading from it - and I've tried the solutions suggested in that thread, none make any difference.

Answer 1

Looks like you're converting from UNICODE to ASCII somewhere along the line...
Have a look at this to get a quick demo of what happens. In particular, pay attention to the ascii derived from inr, versus the ascii derived from unicode...
SELECT
t.n,
ascii_char = CHAR(t.n),
unicode_char = NCHAR(t.n),
unicode_to_ascii = CONVERT(varchar(10), NCHAR(t.n))
FROM (
SELECT TOP (1024)
n = ROW_NUMBER() OVER (ORDER BY ao.object_id)
FROM
sys.all_objects ao
) t
WHERE 1 = 1
--AND CONVERT(varchar(10), NCHAR(t.n)) ='À'
;

Answer 2

I found a workaround that appears to do the trick: I was previously trying to replace the ? in the code with &#63 (took out the ; so that it will show the code rather than the output), which didn't work. BUT it seems to work if I use &quest instead.
One thing to note, it seemed that I was originally incorrect in thinking that the issue was only affecting content being read/displayed from the MSSQL DB. Rather, it looks like the same problem was also occurring with static content being "echo'd" by code in the ASP scripts (I'm more of a PHP guy, not sure the correct term is for ASP's equivalent to echo is). Though the links that were hardcoded as static (rather HTML being dynamically output by ASP) were unaffected. Though chancing the ? to &quest worked for those ones too (hardest part was tracking down the file I needed to edit).