Batch file renaming -

i come little problem :'( : have many txt files , more , more day , need make back-up of them , encrypt them safety reasons made batch script :

@echo off  /r d:\txtwork %%g in (**.txt **.trt) ( certutil -f -encode "%%g" "%%g.bak" echo. >>d:\txtwork\logs\logbak1.txt %time:~0,-6% - made back-up of file - "%%g"  ) 

ok works want make batch decode them , change extension old 1 (from .txt.bak or .trt.bak .txt or .trt ) tried , made :

@echo off  /r d:\txtwork %%g in (**.bak) ( certutil -f decode "%%g" "%%g:~0,-4"  ) 

but didn t work tried

@echo off  /r d:\txtwork %%g in (**.bak) ( set var_1="%%g"  certutil -f decode "%var_1%" "%var_1:~0,-4%"  ) 

it didn't work either. ?

• "%%g:~0,-4" totally wrong;
• to retrieve value of var_1 variable need enable delayed expansion , use !var_1! instead of %var_1% although doing bring problem:
  • certutil -f decode "!var_1!" "!var_1:~0,-4!" expand
  • certutil -f decode ""something.txt.bak"" ""something.txt"" (note doubled double quotes);
• use next set command syntax: set "var_1=%%g" (note first double quote position).

next code snippet should work:

@echo off  setlocal enableextensions disabledelayedexpansion /r d:\txtwork %%g in (**.bak) (     set "var_1=%%g"     setlocal enabledelayedexpansion     certutil -f decode "!var_1!" "!var_1:~0,-4!"      endlocal ) 

however, use parameter extensions follows:

@echo off  setlocal enableextensions /r d:\txtwork %%g in (**.bak) (     certutil -f decode "%%g" "%%~dpng"  )