I am installing a fresh install of Exchange cu8, not an update a straight install. However it takes many hours to install, many more than have previously experienced. It is non Internet facing. The area it takes its time on is compiling assemblies. The ngen.exe retries 6 times each taking around 7 minutes each. Until it errors and continues with the install.

Have disabled certificate revocation check within Internet Explorer and have even added clr.microsoft.com to the hosts files pointing to 127.0.0.1.

Have tried registry keys for speeding up the timeout for crl checks,  buy no joy with that either. 

Is there anything else that can be looked at?

• Edited by Gallaway087 Friday, August 21, 2015 7:11 PM

Hi Gallaway, 

Thank you for your question. 

Is the issue solved? 

When we uncheck it, we could clear IE cache, then clear DNS cache by the following command: 

Ipconfig /flushdns 

For testing, we could remove hots record which is clr.microsoft.com to check if the issue persist. 

If not, please post entire Exchange install log to us for troubleshooting. 

The more details are about Exchange 2013 deployment, we could refer to the following link: 

https://technet.microsoft.com/en-us/library/aa998619(v=exchg.150).aspx 

If there are any questions regarding this issue, please be free to let me know. 

Best Regard, 

Jim