Moved this to the maware section for better attention. Such a brief post really doesn't explain what's happening or where but I assume you are getting popups as per my Google Search for tumri.net advised me.
I copied this from one post I found:
To block tumri.net cookie in Internet Explorer
1. From the Tools menu of Internet Explorer, select Internet Options
2. Select the Privacy tab, and then click Sites. The Per site privacy actions window will be displayed
3. In the Per site privacy actions window, enter tumri.net in the Address of Web site field
4. Click Block
To block tumri.net cookie in Mozilla Firefox
1. From the Tools menu, select Options
2. In the upper section of the Options window, click Privacy
3. In the Cookies tab, click Exceptions
4. In the new Exceptions - Cookies window, enter tumri.net in the Address of Website field and click Disable
Meanwhile you might was to run RootkitRemover, Stinger and Malwarebytes Free, all linked in the last link in my signature below.
After running uninstall the first 2 as they don't self-update.