To follow up on previous life cycle post I’d like to blog a bit on a very interesting issue that has already been acknowledged by Microsoft but yet to be officially documented (in Microsoft public knowledge base).
There is an issue that has been occurring with multiple connections to the same Exchange 2010 mailbox from XP SP3 machines using NTLM authentication.
The problem manifested itself with inability to connect more than 1 client at a time. If users left their Outlook connected to Exchange 2010 mailbox at the office then home connection would fail.
Initially, the workaround found empirically was to set all but one of the Outlook clients to connect using basic authentication. The problem that eventually came up with this workaround is that if the user has opted to allow autodiscover to change the connection settings without prompting them again, the basic authentication setting will be reverted to NTLM each time they restart Outlook.
Upon investigation with Microsoft, it was discovered that the problem only seems to exist when the different machines are connecting to multiple CAS servers, but it cannot be reproduced when connecting to the same CAS server (with all clients connecting via NTLM).
Apparently the resolution until the permanent fix is available may include editing of hosts file to make a machine explicitly connect to a specific CAS server.
The downside to this solution is that if anything happens to the CAS server that someone puts in their hosts file, they will have the potential to lose connectivity to their mailbox.
Apart from that there is another possible workaround that can be implemented (if certain things are in a particular environment):
It is possible to add an A record for the VIP instead of using a hosts file (given Active Directory DNS is used for workstations). Thus internally all machines will use the DNS from Active Directory as an override.
This has not been tested actually but I can’t see anything that may prevent the configuration for seamless work at this time.
There is also a chance the problem will never be resolved by Microsoft as Windows XP has reached EOL for the most part and there shouldn’t be any surprise if that ends up with something like ‘please upgrade your workstations’
Недавно получил и вот только что завиртуалил свеженькую первую бету грядущей Windows 7. Пока, как впрочем и от предыдущего билда, впечатления самые положительные.
В последнее время все больше и больше ощутим такой вот push Microsoft как стремление усилить свои позиции в разных нишах рынка. Я, постоянно работая с продуктами Microsoft, считаю подобные телодвижения более чем правильными, тем более когда эффективная интеграция между продуктами все улучшается.
Yes I know I’m far from being first to share the impressions:) Actually my experience with it dates as back as early November so I was among those pioneers anyway.
