Why EnvVarUpdate corrupts PATH

[Efigenio]

In my installer script, I have issued the following commands.
${EnvVarUpdate} $1 "PATH" "A" "HKLM" ${PATH_EXTENSION_STRING}
In one out of the twenty attempts this command gets corrupts the PATH. I mean that it does not appent the PATH_EXTENSION_STRING but replace it. The fatal result is that almost no software is able to run on this affected machine.

Anyone have any clue why EnvVarUpdate corrupts PATH

[Devasis]

Well I just want to one thing that it happens occasionally or in every twenty attempts. According me the only possible solution for this is to add debugger statements some thing like message box at each and every step of the ${EnvVarUpdate} macro/Function and then notice where it is failing. I hope this will help you to figure out the problem.

[Solomon]

The reason which I found that may or may not be the same reason the corruption of path.

One may be the PATH variable length. Usually the server, type (such as the 2003 server), limit is 2048 characters. Not a hot fix in XP or SP2, it is 1023.


I am still thinking the right thing to do. Count the words or characters in the existing path, then determine what can be done? Also looking at the EnvVarUpdate code to make the fix.

[MrChris-]

This is my first time to hear XP path constraints. But then again, most places I need Windows to install the latest service pack always. If it is a problem, maybe you should check the service pack or set, and then try to limit its presence. Another technique may be used to identify the path and use the variables in the path of the folder in the short folder names.

[Calvin K]

Few weeks ago, I decided not to use EnvVarUpdate tool again and use setx place.
This is working fine for some time, but yesterday the same thing has happened: PATH of the old content is replaced by my stuff. Again, it is only occasional. Therefore, we have the same phenomenon, caused by two different tools. Then I issued within a batch script , and had no problems