This is pdfTeX, Version 3.14159265-2.6-1.40.16 (TeX Live 2015) (preloaded format=pdflatex 2016.5.25)  13 JUL 2023 14:35
entering extended mode
 \write18 enabled.
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**chap2.tex
(./chap2.tex
LaTeX2e <2016/03/31>
Babel <3.9q> and hyphenation patterns for 81 language(s) loaded.
! Undefined control sequence.
l.48 \hypertarget
                 {chapter2}{}
? 
! Emergency stop.
l.48 \hypertarget
                 {chapter2}{}
End of file on the terminal!

 
Here is how much of TeX's memory you used:
 5 strings out of 493027
 119 string characters out of 6134069
 53546 words of memory out of 5000000
 3647 multiletter control sequences out of 15000+600000
 3640 words of font info for 14 fonts, out of 8000000 for 9000
 1141 hyphenation exceptions out of 8191
 5i,0n,1p,673b,8s stack positions out of 5000i,500n,10000p,200000b,80000s
!  ==> Fatal error occurred, no output PDF file produced!