Navigation error when using WV2 to connect to Blazor server app

[jonrmorgan99]

I've been using WV2 for a couple of years to connect customers running my C# apps to purchase/register the apps on my site. All worked well under Net7.

Recently I upgraded my apps and the site to net8. Since then I've been getting reports of navigation failure 500 errors with Status code "Unknown" being logged in my CoreWebView2_NavigationCompleted handler. Customers say they can't connect to the landing page on my site although the page loads fine with same query string in Firefox, Edge and Chrome.

I can also complete end to end test purchases both on IIS and the remote server so it looks as though the issue is WV2/Net8 specific. I'm running WV2 1.0.2365.46 on Net8 and the site is a Blazor server app.

It's not an anti-virus issue as customers report they still can't connect with av switched off.

I've tried various "fixes" including adding this code to program.cs in the server app:

builder.Services.AddCookiePolicy(options=> { options.MinimumSameSitePolicy = SameSiteMode.None; });

which should revert cookie handling to the Net7 policy, but seems to have no effect.

Any insights much appreciated.

[jonrmorgan99]

Here's the request and response detail from customer purchase when the 500 server error is returned

Actual headers sent with request
[accept, text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,/;q=0.8,application/signed-exchange;v=b3;q=0.7]
[accept-encoding, gzip, deflate, br, zstd] [accept-language, es,es-ES;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6]
[priority, u=0, i]
[sec-ch-ua, "Chromium";v="124", "Microsoft Edge";v="124", "Not-A.Brand";v="99", "Microsoft Edge WebView2";v="124"] [sec-ch-ua-mobile, ?0] [sec-ch-ua-platform, "Windows"] [sec-fetch-dest, document] [sec-fetch-mode, navigate] [sec-fetch-site, none] [sec-fetch-user, ?1] [upgrade-insecure-requests, 1] [user-agent, Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36 Edg/124.0.0.0]

Headers in response received
[date, Sat, 04 May 2024 22:47:03 GMT]
[server, Microsoft-IIS/10.0]
[x-powered-by, ASP.NET]

when I run test purchases I get this

Actual headers sent with request
[accept, text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,/;q=0.8,application/signed-exchange;v=b3;q=0.7]
[accept-encoding, gzip, deflate, br, zstd] [accept-language, en-GB,en;q=0.9,en-US;q=0.8] [priority, u=0, i] [sec-ch-ua, "Chromium";v="124", "Microsoft Edge";v="124", "Not-A.Brand";v="99", "Microsoft Edge WebView2";v="124"] [sec-ch-ua-mobile, ?0] [sec-ch-ua-platform, "Windows"] [sec-fetch-dest, document] [sec-fetch-mode, navigate] [sec-fetch-site, none] [sec-fetch-user, ?1] [upgrade-insecure-requests, 1] [user-agent, Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36 Edg/124.0.0.0]

Headers in response received
[blazor-enhanced-nav, allow]
[cache-control, no-cache, no-store, max-age=0] [content-encoding, gzip] [content-type, text/html; charset=utf-8] [date, Sun, 05 May 2024 08:23:14 GMT] [pragma, no-cache] [server, Microsoft-IIS/10.0] [set-cookie, .AspNetCore.Antiforgery.aOczVCVu7s0=CfDJ8E0kudhTb5RImo8Dcstr7Sytq--VMhrlacshCovlNbJOvmA6SjnEe7c4q8czKDz9EjhRZFf91g1P2FoPVVP-tKsf4lSO7_bDWPtCIlYXrm4k0vTlmWD2OEcrzl65mz0xf_rkaarJ10K43lvIsQghrCM; path=/; secure; samesite=strict; httponly] [strict-transport-security, max-age=2592000] [vary, Accept-Encoding] [x-frame-options, SAMEORIGIN] [x-powered-by, ASP.NET]

Still can't track the problem down, although it does look as though the server is blocking the requests. It may be a regional problem as customer error reports I'm getting are all from non UK locations.

Any insights ?