|It does seem like there is some Registry issue. Would have been helpful to get the info you just posted in your last reply in the very first post (you are not even connected, System Restore disabled, etc.). Unless it is "personal", citing the exact URL of that start Page might be helpful.|
The fact that you can "successfully" attempt opening an online image directly (png, gif, jpg, etc) may confirm what I suspected. We could run a few more tests to see if it can directly "attempt" to open a *.php, *.aspx, *..etc, but we already can suspect a problematic Registry entry (or entries, or even missing entry).
Regardless... what to do about a possible Registry problem?
• You can start by running HijackThis, like I suggested in the first place. The program will not make any changes to that computer unless you tell it to. It's main function is to scan (very, very fast) for the computer's present internet/browser configuration, and browser helpers (even hidden ones), and start-up items, and such. It only takes 3 seconds or so (I told you it was fast!). It can save a log of that scan, and that log can be analyzed by knowledgeable folks (for free online), or at least this automatic analyser:
• You are familiar with CCleaner , so you may want to do a Registry check with it (select only one category at a time), but be very careful about making any suggested changes. If you very patiently examine in detail any errors it reports, you may catch a glimpse of the "glitch". Registry Cleaners are notoriously unpopular by people in the know. They are often useless at best, and too often create even more problems, so you must proceed with much caution.
Further suggestions down the line may include:
• Performing a Microsoft Windows System Check (sfc /scannow).
• Performing an inline upgrade/installation (no data is lost, it installs "over itself").