roscore param error

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Hello, I got a problem I haven't resolved yet...

Everything was fine, I was able to run roscore, my roslaunch, etc., but at the next day I ran roscore and gave me the next log problem:

Invalid <param> tag: Cannot load command parameter [rosversion]: command [rosversion roslaunch] returned with code [1].

Param xml is < param command="rosversion roslaunch" name="rosversion" />
The traceback for the exception was written to the log file
No handlers could be found for logger "roslaunch"

I have already tried to source my PATH, but I can't still fix the problem.

Thanks!!