Gfilui

for my bash programming assignment i have to create pipelines to process a file to find some patterns. I am currently using the Windows 10 Ubuntu App terminal. I Wrote the following the following :

echo "Processing Log Files..."
# error is the word I'm looking for in the files
grep error -A 1 logfile1.txt >> filter.txt
grep error -A 1 logfile2.txt >> filter.txt
echo "Done."

But when i run the file with the header #!/bin/sh I get this error:

Processing Log Files...
: Directory nonexistentoder.sh: cannot create filter.txt
: Directory nonexistentoder.sh: cannot create filter.txt
Done.

And when i run the code with the header #!/bin/bash i get this error:

Processing Log Files...
: No such file or directoryer.txt
: No such file or directoryer.txt
Done.

I honestly have no idea of why this happens, i changed the permissions of the files to the following:

drwxrwxrwx 0 root root 512 Mar 20 23:25 .
drwxrwxrwx 0 root root 512 Mar 20 13:59 ..
-rwxrwxrwx 1 root root 316 Mar 20 23:24 decoder.sh
-rwxrwxrwx 1 root root 52247 Mar 19 15:59 logfile1.txt
-rwxrwxrwx 1 root root 33142 Mar 19 15:59 logfile2.txt
-rwxrwxrwx 1 root root 239 Mar 19 15:39 mapping-sorted.txt

Thanks to @steeldriver I found out that the script i wrote had hidden windows characters, since i was using a windows text editor. I ran the following line, and the file had the header #!/bin/bash.

dos2unix scriptName.sh

the script worked afterwards :D