[asp-classic] How to resolve "The requested URL was rejected. Please consult with your administrator." error?

I have faced the same issue using Google Chrome browser. Same website was opening normally using the incognito mode and different browsers. At first, I cleared cached files and cookies over the past 24 hours, but this didn't help.

I realized that my first visit to the website was during the past 10 days. So, I cleared cached files and cookies over the past 4 weeks and that resolved the problem.
Note: I didn't clear my browsing history data