diff --git a/build/conf/nsis/idea.nsi b/build/conf/nsis/idea.nsi
index 7a7adaa54927..aafdf0d0cf93 100644
--- a/build/conf/nsis/idea.nsi
+++ b/build/conf/nsis/idea.nsi
@@ -108,6 +108,7 @@ ReserveFile "DeleteSettings.ini"
     ${EndIf}
   FunctionEnd
 
+
   Function ${un}compareFileInstallationTime
     StrCpy $9 ""
   get_first_file:
@@ -187,19 +188,37 @@ loop:
   Goto loop
 FunctionEnd
 
-Function ${un}DeleteDirIfEmpty
+
+Function ${un}deleteFiles
+  ClearErrors
+  FindFirst $2 $1 $0\*.*
+loop:
+  StrCmp $1 "." next 0
+  StrCmp $1 ".." next 0
+  StrCmp $1 "" done
+  DetailPrint "delete file: $1"
+  Delete $1
+next:
+  FindNext $2 $1
+  Goto loop
+done:
+  FindClose $2
+FunctionEnd
+
+
+Function ${un}deleteDirIfEmpty
+  ClearErrors
   FindFirst $R0 $R1 "$0\*.*"
-  strcmp $R1 "." 0 NoDelete
-   FindNext $R0 $R1
-   strcmp $R1 ".." 0 NoDelete
-    ClearErrors
-    FindNext $R0 $R1
-    IfErrors 0 NoDelete
-     FindClose $R0
-     Sleep 1000
-     RMDir "$0"
-  NoDelete:
-   FindClose $R0
+  StrCmp $R1 "." 0 done
+  FindNext $R0 $R1
+  StrCmp $R1 ".." 0 done
+  ClearErrors
+  FindNext $R0 $R1
+  IfErrors 0 done
+  Sleep 1000
+  RMDir "$0"
+done:
+  FindClose $R0
 FunctionEnd
 !macroend
 
@@ -344,6 +363,7 @@ get_next_element:
   FindNext $1 $2
   IfErrors 0 next_elemement
 done:
+  ClearErrors
   FindClose $1
   Pop $2
   Pop $1
@@ -714,7 +734,7 @@ saveProperties:
   Goto complete
 fullRemove:
   StrCpy $0 $3
-  Call DeleteDirIfEmpty
+  Call deleteDirIfEmpty
 complete:
 FunctionEnd
 
@@ -1255,7 +1275,7 @@ SectionEnd
 
 Function .onInit
   SetRegView 32
-  Call CreateLog
+  Call createLog
   !insertmacro INSTALLOPTIONS_EXTRACT "Desktop.ini"
   Call getInstallationOptionsPositions
   IfSilent silent_mode uac_elevate
@@ -1451,9 +1471,6 @@ UAC_Admin:
 UAC_Done:
   !insertmacro MUI_UNGETLANGUAGE
   !insertmacro INSTALLOPTIONS_EXTRACT "DeleteSettings.ini"
-
-  Call un.CreateLog
-  ${LogText} "un.onInit"
 FunctionEnd
 
 
@@ -1738,11 +1755,11 @@ skip_delete_settings:
   IfFileExists "$INSTDIR\jre32\*.*" 0 no_jre32
     Delete "$INSTDIR\jre32\bin\server\classes.jsa"
     StrCpy $0 "$INSTDIR\jre32\lib\applet"
-    Call un.DeleteDirIfEmpty
+    Call un.deleteDirIfEmpty
 no_jre32:
   !include "unidea_win.nsh"
   StrCpy $0 "$INSTDIR"
-  Call un.DeleteDirIfEmpty
+  Call un.deleteDirIfEmpty
 
 ; remove desktop shortcuts
 desktop_shortcut_launcher32:
diff --git a/build/conf/nsis/log.nsi b/build/conf/nsis/log.nsi
index a04a2ea909e7..59ac8d75f71d 100644
--- a/build/conf/nsis/log.nsi
+++ b/build/conf/nsis/log.nsi
@@ -3,7 +3,7 @@
 var logFile
 
 !macro INST_UNINST_LOGGING_SWITCH un
-  Function ${un}CreateLog
+  Function ${un}createLog
     Push $R0
     Push $R1
     Push $R2
diff --git a/python/educational-python/build/customInstallActions.nsi b/python/educational-python/build/customInstallActions.nsi
index f22aa345d8bb..94eff5022fca 100644
--- a/python/educational-python/build/customInstallActions.nsi
+++ b/python/educational-python/build/customInstallActions.nsi
@@ -6,6 +6,7 @@
 Var internetConnection
 ${StrTok}
 
+
 Function customPreInstallActions
   IfFileExists "$TEMP\python.txt" deletePythonFileInfo getPythonFileInfo
 deletePythonFileInfo:
@@ -129,11 +130,12 @@ loop:
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" "Field $R0" "State" $R3
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" "Field $R0" "Text" "$0"
   ${LogText} "  association: $0, state: $R3"
-  goto loop
+  Goto loop
 
 update_settings:
+  ClearErrors
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" "Settings" "NumFields" "$R0"
-  goto done
+  Goto done
 no_silent_config:
   Call IncorrectSilentInstallParameters
 done:
@@ -147,8 +149,9 @@ Function customInstallActions
 ; info about 2 and 3 version of python
   StrCmp $R0 ${PYTHON_VERSIONS} getPythonInfo
 cantOpenFile:
+  ClearErrors
   StrCpy $internetConnection "No"
-  goto check_python
+  Goto check_python
 getPythonInfo:  
   Call getPythonInfo
   StrCmp $0 "Error" skip_python_download
@@ -159,7 +162,7 @@ getPythonInfo:
   StrCmp $R2 1 "" python3
   StrCpy $R2 $0
   StrCpy $R3 $1
-  goto check_python
+  Goto check_python
 python3:  
   !insertmacro INSTALLOPTIONS_READ $R2 "Desktop.ini" "Field 9" "State"
   StrCpy $R7 ""
@@ -175,15 +178,10 @@ install:
   StrCmp $R2 1 "" skip_python_download
   StrCpy $R2 $R0
   StrCpy $R3 $R1
-check_python:  
-  ReadRegStr $1 "HKCU" "Software\Python\PythonCore\$R2\InstallPath" ""
-  StrCmp $1 "" installation_for_all_users
-  goto verefy_python_launcher
-installation_for_all_users:
-  ReadRegStr $1 "HKLM" "Software\Python\PythonCore\$R2\InstallPath" ""
-  StrCmp $1 "" get_python
-verefy_python_launcher:
-  IfFileExists $1python.exe python_exists get_python
+
+check_python:
+  Call searchPython
+  StrCmp $4 "Absent" get_python python_exists
 get_python:
   StrCmp $internetConnection "No" skip_python_download
   CreateDirectory "$INSTDIR\python"
@@ -204,14 +202,24 @@ skip_python_download:
 done:
 FunctionEnd
 
+
 Function customPostInstallActions
   DetailPrint "There are no custom post-install actions."
 FunctionEnd
 
+
 Function un.customUninstallActions
-  DetailPrint "There are no custom uninstall actions."
+  DetailPrint "customUninstallActions"
+  StrCpy $0 "$INSTDIR\..\python"
+  DetailPrint "install dir: $0"
+  IfFileExists "$0\*.*" 0 no_python
+    DetailPrint "delete python installer"
+    Call un.deleteFiles
+    Call un.deleteDirIfEmpty
+no_python:
 FunctionEnd
 
+
 Function updatePythonControls
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" $R4 "Text" "Python $R2 (installed)"
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" $R4 "Flags" "DISABLED"
@@ -221,13 +229,15 @@ Function updatePythonControls
   !insertmacro INSTALLOPTIONS_WRITE "Desktop.ini" $R5 "State" "0"
 FunctionEnd
 
+
 Function getPythonInfo
+  ${LogText} "get Python info"
   ClearErrors
   FileOpen $3 $Temp\python.txt r
 ; file can not be open.
   IfErrors cantOpenFile
   ${If} ${RunningX64}
-    goto getPythonInfo
+    Goto getPythonInfo
   ${Else}
     FileRead $3 $4
     FileRead $3 $4
@@ -241,12 +251,13 @@ getPythonInfo:
   FileRead $3 $4
   ${StrTok} $R0 $4 " " "1" "1"
   ${StrTok} $R1 $4 " " "2" "1"
-  goto done
+  Goto done
 cantOpenFile:
   StrCpy $0 "Error"
 done:
 FunctionEnd
 
+
 Function searchPython
 ; $R2 - version of python
   ${LogText} "search a Python version"
@@ -254,31 +265,30 @@ Function searchPython
   StrCpy $1 "Software\Python\PythonCore\$R2\InstallPath"
   StrCpy $2 ""
   SetRegView 64
-  call OMReadRegStr
+  Call OMReadRegStr
   SetRegView 32
   StrCmp $3 "" CU_32bit verifyPythonLauncher
 
 CU_32bit:
-  call OMReadRegStr
+  Call OMReadRegStr
   StrCmp $3 "" installationForAllUsers verifyPythonLauncher
 
 installationForAllUsers:
   StrCpy $0 "HKLM"
-  call OMReadRegStr
+  Call OMReadRegStr
   SetRegView 64
-  call OMReadRegStr
+  Call OMReadRegStr
   SetRegView 32
   StrCmp $3 "" LM_32bit verifyPythonLauncher
 
 LM_32bit:
-  call OMReadRegStr
+  Call OMReadRegStr
   StrCmp $3 "" pythonAbsent
 verifyPythonLauncher:
-  IfFileExists $3python.exe pythonExists pythonAbsent
-pythonAbsent:  
-  StrCpy $4 "Absent"
-  goto done
-pythonExists:  
+  IfFileExists $3python.exe 0 pythonAbsent
   StrCpy $4 "Exists"
-done:  
+  Goto done
+pythonAbsent:
+  StrCpy $4 "Absent"
+done:
 FunctionEnd