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Sorry if this is a silly question, but I'm new to all these certificates stuff :)

Let's say I have a digital certificate issued by my company (for email) with:

  • Signature algorithm: md5RSA
  • Public Key: RSA (512 bit)

Is it possible to convert this to use:

  • Signature algorithm: sha1RSA
  • Public Key: RSA (2048 bit)

Or it needs to be recreated by my issuer with the new settings?

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up vote 3 down vote accepted

It needs to be recreated. Public and private keys are made in pairs at the same time.

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As I suspected. Thank you! – Bogdan Nov 22 '10 at 11:29

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