Sporadic error: The file has not been pre-compiled, and cannot be requested

Question

Symptoms: ASP.NET Web Forms website on Azure sporadically crashes and all .aspx page requests fail with this error. The problem seems random and only happens once in a great

Answer 1

I just wanted to post here, because it might be relevant to other people. I had a large legacy project in ASP.NET Framework 4.7/4.8 running in Azure.

I had a lot of problems with the "live" compilation of pages on Azure. With a lot I mean really a lot. Sometimes I hit a page that wasn't precompiled and Azure seemed to exhaust all resources just on the compilation, bringing the whole application down. After a restart it took 8 (!!) minutes before it could handle the first hit. Local it was only like 30 seconds.

During Corona I finally had time to move to .NET Core - and all these problems instantly went away.

Despite that Microsoft says they will continue supporting .NET Framework for a long time, it is clear to me that Microsoft doesn't have any passion for that project anymore. The issues I had in combination with Azure were ridiculous.

I strongly recommend to migrate as soon as possible. Even for a large project it was less painful than I imagined beforehand.