Common Misconceptions

Policies are the same from school to school
Absolutely not. This is a very important point to understand. Each school is free to establish its own policies. This means each school can choose to accept, reject, or modify any of the following as only a short list:
 * Credits accepted for transfer in.
 * Minimum passing scores for CLEP, DSST, ECE, etc. tests.
 * Upper and lower level credit distinctions.

A school will/must accept any transferred credit
Not necessarily. See above. Each school is free to determine its own policies on acceptance of transfer credits. Most schools severely restrict the amount of credits they accept transferred in. The Big 3 accept 120 credits in transfer from a variety of sources, but the credits must still apply towards your chosen degree plan. For example, your 3 credits in underwater basket weaving likely do not apply towards your business administration degree -- though they may be applicable as free electives. Always check with your academic advisor before assuming anything.

Because my academic advisor said it, it must be true
It depends. Sometimes advisors misunderstand the situation, or are just plain wrong. They are human after all. You should always obtain any decision that impacts your academic career in writing, and remember that a decision that negatively impacts you (e.g. refusal to accept a certain course in transfer) can always be appealed. There is no guarantee of a ruling in your favor, however.