Error in load(file) :
bad restore file magic number (file may be able) — no data loaded
in addition: Warning message:
file ‘Deng.Rdata’ has magic number ‘RDX3’
Use of save versions prior to 2 is deprecated

my Rdata was saved with R3.6 and loaded with R3.4
This occurs when the R version used is greater than or equal to 3.5.0 version, and the R version used to read the file is less than 3.5.0

It should be the R version mismatch
Solution: Add version= when saving Rdata and specify the R version at read time