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Windows CRL caching

By default, both downloaded CRLs and OCSP responses are cached by a Windows client. If a
time-valid version of the CRL or OCSP response exists in the cache, the client will use the
cached version rather than downloading an updated CRL or submitting a new OCSP request. 

Caching related configuration is defined in the following registry hive:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\OID\EncodingType 0\CertDllCreateCertificateChainEngine\Config

A binary value of: 

ChainCacheResyncFiletime 

defines when cache will be cleared. 

Force the cache to be cleared:

c:\> certutil –setreg chain\ChainCacheResyncFiletime @now

Force the cache to clear in 1 hour:


c:\> certutil –setreg chain\ChainCacheResyncFiletime @now+0:1

View current cache life time config:

c:\> certutil –getreg chain\ChainCacheResyncFiletime

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