I have tried to install windows movie maker, but error comes that "the procedure entry point wmcreateredre could not be located in in the dynamic link liberarywmvcore.dll.what should I do?

Run Windows Update to make sure the latest files are installed.

Most likely related to the fact you are using a pirated version of Windows 7.
Get yourself legal and then come back and ask for advice.

@Curlyben so you couldn't just assume he had the legal version and write and answer, why u so stopid??
Anyway, I have the legal version, can I have an answer?

@Toegemann, as the OP had already admitted to asking for assistance with an illegal copy of this OS, my comments where justified.

Now what was your issue and did you try running a FULL update as suggested ?