I run Win 7 Enterprise 64bit, SP1. MiKTeX was working just fine until I run Update (Admin) and the update stopped midway saying "internal error". Since then, MiKTeX stopped working: I could no longer open a TeX file, update package repository, run any update. So I uninstalled MiKTeX, rebooted, run CCleaner just in case, and installed MiKTeX 2.9 from scratch (basic-miktex-2.9.6161-x64). The installation was suspiciously quick, I remember in the past spending some good 10-20 min watching folders flying from left to right in the update screen... anyway, once the install was over I decided to run Update (Admin), but only one package could be selected, MiKTeX2.9 (or similar), if I tried to select any other package i would get the message "to install any more packages, close the update and then try again". So I update that one package, then launch the Update again... and I get the usual "internal error". So I am back to square one. Any idea how to fix this? I am not an expert user so please try to be clear if you attempt to answer this question!
If I try to update formats under Settings (Admin), it starts running and then it stops. The log shows:
2016-12-30 15:34:02,801-0500 INFO miktex-makefmt - running 'initexmf --quiet --update-fndb' to refresh the file name database
2016-12-30 15:34:05,406-0500 INFO makex - Creating the etex format file...
2016-12-30 15:34:05,422-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:34:05,469-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on etex.ini.
2016-12-30 15:34:28,329-0500 INFO miktex-makefmt - running 'initexmf --quiet --update-fndb' to refresh the file name database
2016-12-30 15:34:30,918-0500 INFO makex - Creating the latex format file...
2016-12-30 15:34:30,934-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:34:30,965-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on latex.ini.
2016-12-30 15:34:36,871-0500 INFO makex - Creating the pdfetex format file...
2016-12-30 15:34:36,887-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:34:36,918-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on pdfetex.ini.
2016-12-30 15:34:38,663-0500 INFO makex - Creating the pdflatex format file...
2016-12-30 15:34:38,663-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:34:38,694-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on pdflatex.ini.
2016-12-30 15:34:40,038-0500 INFO makex - Creating the pdftex format file...
2016-12-30 15:34:40,048-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:34:40,078-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on pdftex.ini.
2016-12-30 15:34:40,940-0500 INFO makex - Creating the tex format file...
2016-12-30 15:34:40,950-0500 INFO makex - Running miktex-tex.exe...
2016-12-30 15:55:11,097-0500 INFO miktex-makefmt - running 'initexmf --quiet --update-fndb' to refresh the file name database
2016-12-30 15:55:13,642-0500 INFO makex - Creating the etex format file...
2016-12-30 15:55:13,658-0500 INFO makex - Running miktex-pdftex.exe...
2016-12-30 15:55:13,689-0500 FATAL miktex-makefmt - miktex-pdftex.exe failed on etex.ini.