nonvalid digital signature.

I’ve generated a certificate from csr-data, but after I add put it in my IIS, it says there’s something wrong with my certificate. (see attachment)

Intermediate and Root certificates seems to be fine.

[attachment deleted by admin]


Have you checked the knowledgbase article:

If so, then I would suggest submitting a ticket to the support team:



I have exactly the same problem, only started with certs issued today. System is IIS6. Technical support at COmodo have reissued the cert to a new CSR and still the same problem. Get an error in IIS of “The Integrity of this certificate cannot be guaranteed. The certificate may be corrupted or may have been altered” and within the certifcate an error of “This certificate has a nonvalid digital signature”.

I have submitted a ticket but no response.

Anyone else having this problem?

Hi tvirkki,

Seems there was a problem with Comodo’s cert issuing today which they say is now fixed. You’ll need to send a new CSR to with your order number from this morning and they’ll reissue the cert.

Hope that helps.

Please PM me your ticket number and I will look into it if your issue is not already fixed.