What is the difference between the TVOCache and the URLCache in Microsoft CAPI2?

In the CAPI2 log, I’m seeing some CertVerifyRevocation events that have the location TvoCache and some that have the location UrlCache for the validation of the same certificate:

<Event>
  <UserData />
    <CertVerifyRevocation>
      <Certificate fileRef="AC815F8FCDE5524771442A0F619A04DA00C8728D.cer" subjectName="Kaiblinger Harald" />
      <IssuerCertificate fileRef="410DE74321872F90A43E4969C3224A987EDED648.cer" subjectName="Siemens Issuing CA EE Enc 2016" />
      <Flags value="4" CERT_VERIFY_REV_ACCUMULATIVE_TIMEOUT_FLAG="true" />
      <AdditionalParameters timeToUse="2020-05-05T13:42:48.510Z" currentTime="2020-05-05T13:42:48.510Z" urlRetrievalTimeout="PT19.570S" />
      <RevocationStatus index="0" error="0" reason="0" actualFreshnessTime="P2DT3H33M56S" thirdPartyProviderUsed="C:WindowsSysWOW64cryptnet.dll" />
      <CertificateRevocationList location="TvoCache" url="http://ch.siemens.com/pki?ZZZZZZA3.crl" fileRef="A045197D2F9D422F5C163D1F420798D1DD4927C8.crl" issuerName="Siemens Issuing CA EE Enc 2016" />
      <EventAuxInfo ProcessName="OUTLOOK.EXE" />
      <CorrelationAuxInfo TaskId="{A7973502-62E3-4973-8DEE-519E95942DAD}" SeqNumber="16" />
      <Result value="0" />
    </CertVerifyRevocation>
  </UserData>
</Event>

and

<Event>
  <UserData>
    <CertVerifyRevocation>
      <Certificate fileRef="AC815F8FCDE5524771442A0F619A04DA00C8728D.cer" subjectName="Kaiblinger Harald" />
      <IssuerCertificate fileRef="0A9B014FA2E69AB97F6B54B8C07C07B66FA2AA64.cer" subjectName="Siemens Issuing CA EE Enc 2016" />
      <Flags value="4" CERT_VERIFY_REV_ACCUMULATIVE_TIMEOUT_FLAG="true" />
      <AdditionalParameters timeToUse="2020-05-05T13:42:48.510Z" currentTime="2020-05-05T13:42:48.510Z" urlRetrievalTimeout="PT20S" />
      <RevocationStatus index="0" error="0" reason="0" actualFreshnessTime="P2DT3H33M56S" thirdPartyProviderUsed="C:WindowsSysWOW64cryptnet.dll" />
      <CertificateRevocationList location="UrlCache" url="http://ch.siemens.com/pki?ZZZZZZA3.crl" fileRef="A045197D2F9D422F5C163D1F420798D1DD4927C8.crl" issuerName="Siemens Issuing CA EE Enc 2016" />
      <EventAuxInfo ProcessName="OUTLOOK.EXE" />
      <CorrelationAuxInfo TaskId="{A7973502-62E3-4973-8DEE-519E95942DAD}" SeqNumber="8" />
      <Result value="0" />
    </CertVerifyRevocation>
  </UserData>
</Event>

I can’t find any documentation about the difference. Can someone explain the difference?

Tvo here stands for Time Valid Object, we can find references about TVO on this documentation: CryptGetTimeValidObject (Wincrypt.h / Cryptnet.dll)

The CryptGetTimeValidObject function retrieves a CRL, an OCSP
response, or CTL object that is valid within a given context and time.

The Cryptnet dynamic link library implements a time valid object (TVO)
cache that is used to support the CryptGetTimeValidObject function.
The cache is used by a process-global TVO agent […]

The TVO agent supports retrieval of TVO objects on-demand or by auto-update.

While it’s not a documentation about the events you mention, I think it’s safe to assume that it simply means the CRL was found in the TVO Cache.