It's possible you just can't do this. PE and PP are two different programs.
You should be able to import a Premiere Elements file. See this for documentation of this feature.
We need more information if we're going to help. Begin by answering the questions here.
Also, tell us what effects you're using in the Premiere Elements project, since it seems that the error is in the conversion of an effect.
Welcome to the forum.
When the PREL comes from a version of PrE, that is rather contemporary with one's version of PrPro, it should Open fine. If not, try to Import it into a similar Project. Now, there ARE some caveats:
- PrE has some functions that do not exist in PrPro, such as Instant Movies/Themes, and those can cause issues.
- PrE has some 3rd party Effects and Transitions, that do not exist in PrPro, but PrPro should not crash, only alert you to those. However, a few have caused some major issues.
- There could well be other issues, that I am just not remembering.
As a test, create a simple Project in PrE, and Save. Open (or Import) that PREL into PrPro, and test.