Compare the situation that has the problem to a similar situation or environment without the problem, and you should be able to find a difference. The difference leads to the cause of the problem, or at least to an area to be investigated. You must, however, make the comparison before you can see the differences that form the clues to the problem and thus the solution.
Compare the environment; the difference may be here. For example:
"It works on Joe's PC, but not on mine."
"I just upgraded the operating system."
"I bought a new hard drive."
"I upgraded to a newer version of R:BASE."
"I swapped memory."
"I just installed a new operating system update."
Compare the processes; the difference might be in the action or activity. For example:
"My program is running slower than it used to."
"The totals in my report are much larger than they used to be."
"My program used to return to the menu, now it leaves me at an R> Prompt."
"It only happens the second time I do it."
"I modified my program, just a little bit."
Make a time comparison; the difference may be connected to the time of day. For example:
"The network always slows down at lunch time."
"At 9:00 every morning I get kicked out of R:BASE."
"It only happens when Mary is printing the Sales Report."
Compare the problem with a similar situation. For example:
"It prints to the screen, but not to the printer."
"It works from the R> prompt, but not in my application."
"It works in the sample database, but not in my database."
"It works when my database is local, not when it is on the network."
Sometimes it is hard to identify a difference. In fact there can be many situations with no apparent difference or change at all. This may be the time to contact someone who can offer a solution or suggest other areas to check.
