Calibre stopped working after an update

[timddeb]

Windows 7 home 64 bit. Service Pack 1. Calibre stopped working after some updates in Windoze, but I didn't notice it until a little while later as I was only halfway through reading the books I had uploaded. I have tried 32 bit, and v 1.48 with always the same error notice, Python terminated unexpectedly.
Yes I know I should use ubuntu, but I need Band in a Box, and the experience was not good when trying to run it with various doodads and add ons.

[Kovid Goyal (kovid)]

Post the full error message, and follow the steps to run calibre in debug
mode here:
http://manual.calibre-ebook.com/faq.html#calibre-is-not-starting-on-windows

 status incomplete

[timddeb (unbuntu-s)]

full error message is
Pytho function terminated unexpectedly
[Error 5] Acces is denied:
u'C:\\Users\\Tim\\Appdata\\Local\\Temp\\calibre_r9otih'(Error Code: 1)

[Kovid Goyal (kovid)]

You have something on your computer blocking calibre from accessing its
temporary files, most likely an antivirus program.