I lost / forgot my Microsoft Office Product Key / Serial Numbere. How can i find it on my computer?

I friend called me today. He wanted to re-install his Computer, but was able to find his Office 2010 product key any more.

How-I-fixed-it:

Using the Freeware Tool ProduKey by NirSoft you can read out the Product Keys or Serials of many Microsoft products installed on your Computer.
http://www.nirsoft.net/utils/product_cd_key_viewer.html

Here's a list of supported programs:

Microsoft Windows 98/ME

Microsoft Windows 2000

Microsoft Windows NT

Microsoft Windows XP

Microsoft Windows Vista

Microsoft Windows Server 2003

Microsoft Windows 7 (Doesn't work with Microsoft Volume Licensing)

Microsoft Windows 8 (Doesn't work with Microsoft Volume Licensing)

Microsoft Office 2000 (Only ProductID is displayed)

Microsoft Office 2003

Microsoft Office 2007

Microsoft Office 2010

Microsoft SQL Server 2000

Microsoft SQL Server 2005

Microsoft Exchange Server 2000

Microsoft Exchange Server 2003

Visual Studio

Office Home and Business 2010 Access keeps prompting for product key every startup, Problem with Access 2007 runtime engine, msain.dll corrupt or missing

I have Office 2010 Home and Business an my Computer and things for OK for a long time. My ERP-Software which uses Access 2007 runtime engine was up and running for Ages.After installing a new time management software which (Zeitplan), which also seems to be based on Access runtime, problems started.

Starting my ERP-Software failed. An error prompt said "missing or currput msain.dll". Next time it suggested to start Access in Safe Mode, but that did not fix the Problem. The msain.dll was were i expected it to be (OfficeDir\1031). Downloaded the dll from the Internet and replaced the existing one. No changes.
Re-Installed my ERP-Software. No changes.

Did a repair on Office 2010.
No my ERP-Software started to start, but then the Access 2010 splash Screen was shown and it prompted me to enter my Office 2010 Product Key. Entered the key, it was shown as valid, Office activated itself OK. But after a few seconds, i was prompted for the product key again. And again.  And so on.... (Word and Excel did not prompt on Startup. Thei Help box said, they're activated).

I then had a look on the Internet and found out, that Office 2010 Home and Business Edition does not include Access.

How-i-fixed-it:
I found the right hints here (in German): http://www.dims.de/blog/?p=530

I removed Access from the Office 2010 Installation (Control Panel->Add/Remove Programs->Office 2010->Change). I also uninstalled the Access 2007 runtime.

I then re-installed the ERP-Software (which also installed the Access 2007 runtime again).

After that, the ERP-Software was running fine (and also the time Management software). No more product key prompts.

Some other threads about never-ending-product-key-prompt:

http://answers.microsoft.com/en-us/office/forum/office_2010-office_install/after-every-pc-reboot-office-2010-keeps-asking-for/87e2cac0-d8cb-432b-a3d9-8721edf12487?page=1

http://answers.microsoft.com/en-us/office/forum/office_2010-office_install/why-do-i-need-to-enter-product-key-each-time-for/37ef2acf-f6a9-4122-9f1a-f31c815aabf1

Publisher 2010 won't save / export PDF nor XPS any more

After updating my system to Windows 8, Office 2010 Publisher quit saving files as PDF and XPS. The error message was:
"Publisher cannot save the file" or in german "Publisher kann Datei nicht speichern".
On a different computer the same file saved as PDF without problems.

How-i-fixed-it:
I found the right hints how to fix it here:
http://answers.microsoft.com/en-us/office/forum/office_2010-office_other/publisher-2010-error-when-try-to-save-a-file-as/e2df6b52-0359-447d-8b5d-7d4545052ea3

I changed my default printer to a different one than before and suprisingly  PDF and XPS export in Publisher was working fine again.