IPsec has gone into block mode

We have a single Windows SBS2003 running exchange, which when recently restarted, could not ping / access any other IP addresses on the network. On looking at the event log, I noticed that an error reported that IPsec had gone into block mode, and on researching this, established that we should dissable the IPsec service and reboot the server.

This we did, and sure enough it resolved the issue.

My question is, why would this suddenly happen, and do we need IPsec running on the server.

We use OWA, RDP, and SMTP which are all currently working fine.

Any advice would be welcomed.

Many thanks.
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

It's due to a race condition where another serivce reserves the ports before IPSEC does. Issue and fix documented here:


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.