Salesforce Apex: An unexpected error occurred

I got this when I defined a for loop as follows:

for (i=0; i<collection.size(); i++)

The fix is to correct the definition as follows:

for (integer i=0; i<collection.size(); i++)

Epson Status Monitor disappears after installing Windows 8.1

Problem

After installing Windows 8.1, the Epson Status Monitor disappeared. Selecting Printer Preferences would bring up the unhelpful generic Windows info.

The Epson Status Monitor is a rather antiquated piece of software that is still used with the latest Stylus range of printers. Without it, you can't check ink levels or get detailed information about printer errors.

Solution

1. Open Devices and Printers
2. Right-click the printer and select Printer Properties
3. Click the Change Properties button
4. Select the Advanced Tab
5. In the Driver dropdown, change the selection to use the correct driver. In my case, I had to switch from "Epson ESC/P Standard 3 V4 Class Driver" to "EPSON NX130 Series".