When a problem with TeamCity occurs, there is a number of places to look for information:
Check Known Issues and Common Problems.
Visit the TeamCity forum — you can search the forum to see if anyone else has experienced your problem. Our forum's user base is quite active and is a good place to find support or start threads.
TeamCity issue tracker — check if somebody has already reported your problem. If the same issue exists, please vote for the issue. If you are sure you have faced a bug, please collect the relevant data about the problem and post a new issue to the tracker. Be sure to include the TeamCity version, describe where exactly you see the problem, and what actions were preceding it. If relevant, please describe your environment (OS, web server, TeamCity distribution used, how TeamCity is set up, and so on).
Contact us to report an issue or ask a question using the general guidelines described.
If you own Enterprise TeamCity license and need to submit information that is not meant to be public, you can also contact the development team via this online form or feedback email).
To speed up the resolution of your problem, make sure to:
include the affected TeamCity version;
include detailed exact error messages, logs, screenshots;
mention all related postings on the topic.