I solved a mysterious bottleneck last night while working with large string values in MS Access. My VBA code was reading a file to a string variable, checking several values near the beginning of the string, and then manipulating and saving the string to the database.
Oddly, one of the slowest parts of my code was the several InStr calls that were only checking the first few hundred bytes of the string. I could alleviate part of the problem by copying the beginning of my file to a shorter string value, but in so doing I also noticed unexpected results from the InStr return value.
If you ever have to do a case-insensitive array sort in PHP, you will eventually notice that the results don’t match the MySQL latin1_swedish_ci collation. They just aren’t the same. The difference comes from a set of six characters that fall between the upper-case and lower-case alpha characters of ISO-8859-1.
Specifically, [ \ ] ^ _ ` are the troublemakers. A simple example would involve sorting the phrases “Hello” and “[Hello]”. In MySQL, “Hello” comes first. In PHP, “Hello” comes last.
If this is driving you crazy, all you will need to do is trick PHP into using an upper-case sort instead of a lower-case sort.
February update cycle again sent my server into a reboot loop, shutting down all services until I could diagnose the problem on site.
Following the same steps as in my previous post, I switched the boot choice to Safe Mode, and observed another boot failure. This time instead of getting into the weeds of troubleshooting the update system with a second Safe Mode boot, I decided to let the server go back to the normal boot mode, because some other websites have reported this as a good solution.
In this case, the failed Safe Mode boot followed by no other action did successfully restore the server.
After reviewing the Event Viewer logs, I could only find a repeated Event ID 1074, “TrustedInstaller.exe has initiated the restart”. KB2992611 and KB890830 both installed successfully before the loop, then KB4502496, KB2822241, and KB4537814 installed after the loop.
My current recommendation is to disable automatic updates for Windows servers and only perform update checks while on site. Also, run the update check twice in a row. The servicing stack update from December didn’t show up until after recovering from the reboot loop and then checking again for more updates.
After linking two local Excel files by a simple reference to a cell in another workbook, I began seeing an ominous error:
SECURITY WARNING Links to external sources could be unsafe. If you trust the links, click Update. Click for more details.
This behavior was observed in version 1907 of Excel from the Office 365 software package.
Warnings of this nature should be taken seriously. In this case, however, the message has been seriously mislabeled. Clicking into the details brings up an ancient Help page for Excel 2007. Searching for similar situations online brings up some misleading instructions.
If you are experiencing the situation described above, continue reading below for a simple workaround and more background information.
Someone attempted a very noisy attack against my router’s built-in OpenVPN server today. While there was no chance this person could guess my encryption parameters to gain access, he or she did manage to cause a denial of service.