Texmaker and TeXstudio ⇒ No new pdf creation after updates.

[peterb]

I relocated my question from ''general'' to here. Sorry for the confusion.

Hello all,
I recently updated (on Windows10) miktex and texmaker to the latest releases. Since then all I get from texmaker is the .bak file which shows my latest text changes but no updated pdf file is created. There are no error messages in the texmaker logfile. It just ends with ''created xxx.pdf'' (which is the xxx.pdf.bak file).
I deleted miktex and texmaker several times and installed them again in the correct order (first miktex and then texmaker). No improvement though.
Before I updated miktex and texmaker all worked smoothly, no problems at all.
I hope someone can help.
Thanks in advance, Pete

By the way, when I create the ''hello world'' app I get the error message ''no log file''.