Hi there!
This is what worked for me:
1) Go to the HP Support page at:
http://www8.hp.com/us/en/support.html
2) Click on "Drivers and downloads".
3) In the "Find by product" section, enter your product name or model. In this case, "f4180".
4) The search will yield one match, which is the F4180. Click on the link "HP Deskjet F4180 All-in-One Printer".
5) You will be prompted to inform your operating system, which I assume is the same as mine (Windows 7). Be careful to inform the correct number of bits (32-bits, 64-bits). After that, click "Next".
6) In the section "Step two: Select a download", click on "Driver - Product Installation Software". When I wrote this answer on August 7, 2013, there was only one available download, which was listed as:
"2009-10-20 , Version:13.1.0, 245.67M"
But the file's name after you hit "download" is actually:
"DJ_AIO_NonNet_Full_Win_WW_130_140.exe"
7) Download this software and run it. The installation wizard should open after you run the file above.
8) Once the wizard is up and running, click on "Install other software" and you will be given the option to install the OCR I.R.I.S.
9) Follow the instructions on the screen. Once you are done, restart your HP Solution Center and try to scan documents again.
10) After you click on "Scan a document", you will be given the usual options (.tif, .pdf, etc.) but in addition, you will have the option "OCR to Wordpad", which means everything went well and you are ready to go!
I hope I have helped!