Issue while trying to install Security update on Exchange 2013 CU 23

Hello Everyone.

I am trying security update KB4536988 in order to mitigate cve-2020-0688. We have total 10 servers out of which 4 are Exchange 2010 sp3 on which I was able to install RU 30. We also have 6 Exchange 2013 servers all with CU 23 installed 3 of which are CAS servers and rest 3 are Mailbox Servers. I was able to install this security update on other 5 servers but when I wanted to install this patch on the sixth server, I started facing the problem.

The installation exits abruptly few seconds after initiation prompting me to select msi file and gives me a message "The installed product does not match the installation source." In use source I can see it is looking for "Exchange 2013 CU 18 msi file". As it has CU23 installed, I tried to point it to CU 23 msi file but it ended up with another error "The file "C:\cu23\exchangeserver.msi" is not a valid installation package for the product microsoft Exchange Server. Try to find the installation package "exchangeserver.msi" in a folder from which you can install Microsoft Exchange Server" even though I was not prompted for anything as such on any of the other servers.

I also tried by copying Exchange 2013 CU18 files on this server but that did not help either.

If anyone has come accross this error. Please help me understand the underlying problem and fix it for once.

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Basheer Syed