RCMS requires that your browser "allow cookies". Cookies allow the websites to treat your computer as a returning visitor, otherwise it has no way of knowing if you're a new visitor every time you view another page on the website. Interactive websites usually require cookies, or else they must place a unique identifier in every link on their site to accomplish the same goal, but that doesn't allow you to re-visit the page the next day and have it be in the same state, so cookies are indeed a much better option for most websites.
How to enable your browser's cookies and additional information can be found here.
Cookies contain information that websites have gathered about you and stored on your computer as small text files. Most of these files are completely harmless, but others store private details like where you went, what you did, and any personal information you gave. Websites may also allow other sites (their advertisers, for example) to store third-party cookies on your computer. Sometimes it may be necessary to delete any stored cookies if they are interfering with the sites you are working on.
How to clear your browser's cookies and additional information can be found here.