Here is a hot issue between one hotfix and web application.
If you have a web application running on windows 2003 and windows 2008. and using AMYUNI PDF Converter (or other same kind)to convert documents to PDF. This has no any problem at all. After you installed KB2347290 you will unable to use that printing software. Now users (who access via web browser) hang when the web application tries to access the PDF printer.
If you remove KB2347290, the web application will work fine again.
Here is a workaround for now:
1. If your application is ASP.NET or WCF service running under IIS and your web.config has <identity impersonate="true"/>, commenting this line will resolve the problem.
2. If your application running as a CGI under IIS, set the following CGI impersonation option: cscript adsutil.vbs SET w3svc/CreateProcessAsUser false
KB2347290 MS10-061: Vulnerability in Print Spooler Service could allow remote code execution.
Edit: We have released a hotfix for it, please apply this hotfix if you encouter the same issue: