Sunday, February 21, 2010

you receive microsoft exchange is unavailable

this is an old trick but I thought it might worth to mention, if you open your outlook that has an Exchange server profile and get the error: microsoft exchange is unavailable

this is caused because no gateway has been configured in the tcp ip properties in the NIC, add any gateway and your outlook should work.

extra technology stuff at

we are proud to announce our corporate blog, me and fellow consultants at ingazat are blogging regularly at the corp blog, more technical and deep infratructure stuff are there from other fellows, I highly recommend that you follow and visit it.

cannot login to CWA, clock synchronization error

This is very quick post,
if you cannot login to CWA and you get an error that the clock is not synchronized then propably you are using a SIP domain that is different than your internal domain name, please make sure to add the http SPN to your CWA account in the form

Friday, February 5, 2010

OCS DNS and certificate Calculator

Have you ever wondered what is the DNS records that should be created for OCS on internal DNS servers and External DNS servers, to what they should point and what are their configuration.

Have you wondered how you can use a single certificate to support OCS deployment for CWA, FE,Edge and use single certificate.

you can use the attached excel sheet, the input is the follwowing:
- Internal DNS name.
- External DNS name.
- Servers names and External Host records for individual services like (the host records name that will be used for web conferencing..etc).

the output is in 2 sheets, 1 sheet incldues all of the external and internal DNS names, where they should be created and what is their configration.

the other is the list of the certificates, either they should be internal or external and what is their common name an SANs.

if you have any feedback please send it to