Weird Error At Runtime

[mailler0xa]

Hello there, Today I have come across this weird issue but it continues running regardless.

==> /home/launcher/.axiom/tmp/subdominator+03-11_17-00-36-4/logs/recon10 <== System.InvalidOperationException: The character set provided in ContentType is invalid. Cannot read content as string using an invalid character set. ---> System.ArgumentException: 'utf8' is not a supported encoding name. For information on defining a custom encoding, see the documentation for the Encoding.RegisterProvider method. (Parameter 'name') at System.Text.EncodingTable.InternalGetCodePageFromName(String) + 0x235 at System.Text.EncodingTable.GetCodePageFromName(String) + 0x78 at System.Text.Encoding.GetEncoding(String) + 0x28 at System.Net.Http.HttpContent.ReadBufferAsString(ArraySegment1, HttpContentHeaders) + 0x96 --- End of inner exception stack trace --- at System.Net.Http.HttpContent.ReadBufferAsString(ArraySegment1, HttpContentHeaders) + 0x14e at System.Net.Http.HttpContent.ReadBufferedContentAsString() + 0xa4 at System.Net.Http.HttpContent.<WaitAndReturnAsync>d__82`2.MoveNext() + 0xcf --- End of stack trace from previous location --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() + 0x1c at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task) + 0xbe at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task, ConfigureAwaitOptions) + 0x4e at Subdominator.SubdomainHijack.<IsFingerprintVulnerable>d__15.MoveNext() + 0x346 --- End of stack trace from previous location --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() + 0x1c at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task) + 0xbe at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task, ConfigureAwaitOptions) + 0x4e at Subdominator.SubdomainHijack.<IsDomainVulnerable>d__14.MoveNext() + 0x35b --- End of stack trace from previous location --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() + 0x1c at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task) + 0xbe at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task, ConfigureAwaitOptions) + 0x4e at Subdominator.Program.<CheckAndLogDomain>d__7.MoveNext() + 0xf9

More notes The instance has 650K-700K subdomains.