Background

But this one in particular has been significant for some, where CF won't start. Again it's only if you have CF set to use FusionReactor (or any other monitor that relies on a certain java "instrument" library). It also ONLY happens on Windows (not Linux nor in containers/docker images--which complicated a bit my finding this root cause/bug and resolution).

Before explaining and solving the problem, note that if you run CF as a Windows service, when it fails to start (for this or similar reasons), there is nothing in the CF logs to explain it--nor in the Windows Event logs, despite what the error in the service startup pop warning says.

Instead, to see what's really happening, you can go to the Windows Command prompt, and run the cfstart.bat found within your CF installation folder, such as:

If you have this problem, you should see it provide this error:

And FWIW, this problem HAS happened for some people even with CF2025...though it's not happened consistently, like this change in CF2023 update 25.

And back then or since last week some people have proposed various workarounds, which I found less than satisfactory because of factors that I will explain shortly.

The root cause bug: new truncation of a path cf sets

First, let me share what I have discovered to be the root cause (and a new CF bug, I would assert).

As of this CF2023 update 25, at least--and on Windows--CF can easily end up TRUNCATING a path environment variable which it sets internally.

The behavior of cf manipulating the path it sets for itself is not new, though few likely have ever noticed it. I'll show you here how cf (even before the update) appends some CF folders to whatever is set (at CF startup) as the Windows system "path". What's new is the possible truncation.

You can see this modified path for yourself (in a running CF instance) by outputting the CF variable:

The issue is that if the windows path value is already long, then the new problem is that it gets truncated. Let me demonstrate (and you can do the same).

BEFORE Update 25

Don't focus on the first dozen or more values. They are simply what I have in my Windows system path (due to various software I've installed).

Note instead the last few folder names:

These are folders which CF has appended internally, for cf's use only, to be clear. They were not on the original path.

And notice especially that last folder, D:\ColdFusion2023\jdk-17.0.20\bin. That D:\ColdFusion2023\jdk-17.0.20 is the java home as set in my CF admin/jvm.config file. Yours may well be the coldfusion2023/jre folder. Either way, what matters is to notice CF had added a \bin to that, and stuck that folder there at the end of the path it's created, in addition to those other few it also added before it, for its internal use. Again, CF has been doing this for some time.

AFTER update 25

Notice how at the end it's clearly TRUNCATED! And the number of characters here is 254. So somehow, something in CF is newly truncating this modified path (that it's creating internally) at 255 chars, which can be exceeded easily if the Windows path that it starts out with has more than several folders already.

Most important, note that now-truncated path does NOT end with a pointer to that bin folder within the CF java home value. And THAT is why FR (or other java monitors looking for that instrument library) fail, because that's found in a file called instrument.dll which is located in that bin folder. How unfortunate, this new truncation, and SO tricky a challenge to have discerned!

Finally, one MORE subtlety about this appending is that I determined that CF appends its additional folders ONLY if the incoming path it finds is non-empty (and not null). Those two facts were complicating my attempts at various solutions and on different machines.

So, that's the background and root cause. How can we FIX this (to be able to run FR or things like it with CF2023 u25, until Adobe fixes the truncation problem)?

Workarounds that I DON'T recommend

I'll note first that some people (and now even Adobe, as an update since my original post) have proposed things like changing their Windows system path to hard-code prefixing of the path to name that bin folder for the CF java home (because they found that did "work").

That's not only not necessary (as I will show) but it can have unexpected ramifications. First, if you put the Java folder that CF uses on the front of the system-wide path this way, but then have some other program that relies on finding a DIFFERENT java version later in the path, that other app will now fail.

Also, if you later change the java version that you have set as CF's java home, then you would need to remember to change this...otherwise CF will now fail after you that Cf Java home location, though it will be a different error:

I'm documenting this error now, as Java is due to be updated again on Oct 20. So folks following that advice (to tweak the system path to first name the Java folder instead) could face this new problem, where "cf won't start"--but for this other reason, in days and weeks to come.

Finally another suggestion some others have made (to solve this instrument library problem) entails changing the user running CF (thus getting a different "path"), but doing that can have other undesirable ramifications if you're not careful (especially about security, permissions, etc.)

The workaround I recommend, for now

Again, until Adobe may resolve this seeming bug, here is what I propose folks can do, which seems safer than those above, and is pretty simple--though it will take some explaining, to benefit those who may not be too familiar with a couple of things.

To be clear, I am NOT proposing that you touch the Windows system path.

Instead, I offer two approaches to modify the path that is a) ONLY for CF and is b) something that will work regardless of subsequent changes you may make to the CF java home value. And I offer here both how to do it if you are starting CF at the command prompt (such as for testing) and if you are starting CF as a Windows service.

In either case, I'll propose you set the path that CF (alone) uses, to be some simple string. (It can't be the full path, because of the truncation problem. And it can't be null, because I explained above how CF doesn't even do the appending needed--to name that java home bin folder--if it finds the incoming path to be null/empty.)

Instead, it can literally be any string, like just xx (yes, literally that string, as I'll explain why). Ugly, yes, but it's a short-term hack we're implementing here.

Workaround a: if starting CF at the command line

While you may run CF as a service normally (which I cover below), you may only run CF from the command line--or perhaps you've been doing that as part of some other workaround to this problem. Here's mine. (Powershell folks should find all that I say to be easily translated if using that.)

So if you are starting CF from the command line, you could use:

Now put the FR javaagent value back in place, and try starting CF again. This is they key test: does cf now come up?

Note that to stop CF (when you've started it this way at the command line), you could technically just close the command prompt window or logoff, but to keep the terminal window open just use ctrl-c (while your cursor focus is in that command prompt). In a moment (perhaps a few) you should see messages appear indicating that CF is shutting down. (If not, hit ctrl-c again a time or two.) Then you should see it ask finally if you want to terminate the batch file (cfstart.bat). Choose "y" for yes.

Let me know if somehow you find that CF does NOT start even after this change. (There are little mistakes one can make. I can't anticipate all of them here.)

Workaround b: when running CF as a service

But what if you're running CF as a service? Setting the path at the command prompt won't help--and again I am NOT recommending we change the system path--but I suspect people resorted to that as seemingly their only option. It's not.

Instead, it's possible to set the path value FOR THE CF SERVICE itself. You've likely never needed to do it, but it's a simple registry tweak--a single new entry defined for the registry key which holds the CF service definition, which by default would be found within:

Anyone familiar with regedit can find that (or you can find help online, or one can even use the command line "reg" tool to automate this). Note that we can define the "path" for that service (which can be a cool trick for other needs). We do that by defining it as an "Environment" variable for the service (again, not something one normally needs to fiddle with).

But it's really simple. We'd just want to create (for that service defintion) a new "multi-string value" (aka a "reg_multi_sz" value), with the name:

and the value:

I know that looks weird, but trust me on this (I explained above why I'm using xx and not empty string/null). I show how to use the Windows "reg" command to automate this, in a moment.

(As an aside, while using the regedit UI to add this, note that if you don't put an empty line after that value, you'll get a pop up "warning" saying "Data of type REG_MULTI_SZ cannot contain empty strings. Registry editor will remove all empty strings found." Just click ok on that, and it will add an empty line to the value (which doesn't make sense for the warning message, but oh well.)

And that's it.

Now try to start the CF2023 service, even with the javaagent for FR (or any other affected monitor) in place. It's worked for me on multiple machines.

Of course, fiddling with the registry is risky. I'm going to assume readers here are comfortable with that. We're just adding one key, after all.

Reg command variant for that workaround b, tweaking the service definition in the registry

With that context above, I now offer the "reg" command approach for adding this reg name/value pair, for those who may prefer to automate that. You would run at an elevanted/admin command prompt.

Of course, this presumes your CF Windows service has this default service name, as I show affecting here:

I should add also that if you may have created additional "instances" in your CF2023 (which is a feature supported by CF Enterprise and Developer editions, but not Standard edition), then you would need to apply this reg tweak to the service definition for each instance (which would be sibling keys/sections under that HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ location, where all Windows services are defined.)

Finally, the reg command to REMOVE this reg key (which we're adding solely as a temporary workaround, until Adobe fixes the real root cause problem) is this (again, run at an elevated command prompt):

And remember to repeat that for multiple CF2023 services if you created that new Environment key in more than one.

I'll leave powershell users to implement their required variant using this as a guide.

Hope this works: let me know if it does not

I was thrilled to finally find the root cause for this problem, and to be able to offer what seems a "simple" and safe workaround. I'd been working on it off and on (between client engagements, and even in evenings) for a few days. So glad to have first the clear ROOT CAUSE problem, and then to offer some workarounds.

Let me know if it works for you.

And of course if somehow this doesn't work, either add comments below or if necessary reach out to me for support via the contact info at carehart.org/consulting. We should be able to resolve any issue in less than 15 minutes (my minimum billable time). But I won't track the time as billable if we discern something wrong with what I have proposed here. I'm just trying to help everyone.

I will now go report this to Adobe (well, I will add a pointer back to this post on a tracker ticket someone opened today.)

Updates (since the original post)

I was exhausted after spending nearly all day the day of this post competing the research, testing, and documenting of this here. But with the light of day I've thought of some things to bolster the post. And as anyone may share feedback I will update it. If you may want to keep track of updates:

• Sep 30: I can confirm that this problem does NOT happen when running a CommandBox implementation of CF2023 update 25, even on Windows. While the CF within that does also append something to the internal path the bin folder under what it deems to be the JVM used for the instance.

  But more interesting is that I confirmed that (on the same machine that had the long path discussed in the post above) CommandBox does NOT truncate the path it then set (which is indeed the entire detected Windows path plus that one jre bin folder). So again it's somehow unique to CF itself--though note that I'd shared above how it happens only on Windows.

  I have some other install variations I want to explore, as there may be still other situations where this error "does not occur even with CF2025 update 25 on Windows". I have confirmed it happens with either the full or zip install options for CF (on Windows).

• Sep 30: I went ahead and added the reg command needed for automating the workaround involving addition of the new key/value pair to the Windows service definition for CF2023. I show both adding and removing it, for when Adobe (we hope) resolves the root cause bug.

• Oct 6: Agh! Matt G kindly brought to my attention in a comment below a mistake I made in my offered "reg" lines (to add or remove the path set for use with the CF Windows service). He noticed I had a VERY unfortunate typo of "Envrionment" for "Environment". Yikes!

  Given that no one else raised it, I hope that just means no one else had used that reg approach (in which case the tweak wouldn't do what it was supposed to). To be clear, I really HAD tested it...so I don't know when or how that mistake got in there! But thanks, Matt. Now corrected.

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