Roger Cigol

Why would this kind of problem mean that only my application is affected? When the problem happens it is still possible to read and write files to the directories using windows explorer (eg right click and create a new text file).

Auto run: If I look for coloured entries - which are the ones with "not verified"..... In Services I see one: Sense Windows Defender Advanced Threat Protection Service: Windows Defender Advanced Threat Protection service helps protect against advanced threats by monitoring and reporting security events that happen on the computer. (Not Verified) Microsoft Corporation C:\Program Files\Windows Defender Advanced Threat Protection\MsSense.exe Mon Feb 10 16:31:35 2025 In Drivers I see three: BthA2dp Microsoft Bluetooth A2dp driver: Bluetooth A2DP Driver (Not Verified) Microsoft Corporation C:\Windows\System32\drivers\BthA2dp.sys Sat Dec 7 09:07:47 2019 BthHFEnum Microsoft Bluetooth Hands-Free Profile driver: Bluetooth Hands-Free Audio and Call Control HID Enumerator (Not Verified) Microsoft Corporation C:\Windows\System32\drivers\bthhfenum.sys Sat Dec 7 09:07:47 2019 Adobe Type Manager File not found: atmfd.dll The first two are in subcategory: HKLM\System\CurrentControlSet\Services The last one is in subcategory: HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Font drivers

Running SFC did not sound dumb to me (either at the time you posted it, or now). This was done at end of January, after we had done a full "check for updates" iteration round a few times (until it said "all up to date").

So is this suspect driver related to file handling ? or could it be any driver on the machine ?

Thank you, Kas. I have downloaded WinObjEx (exe) and run it. I click on the search (magnifier glass) icon and then enter MyMutex1 and click on Find. It says no objects found. I get the same result if repeat but with search only for "Mutant" in the drop down.

@Kas Ob. My actual app is a 32 bit exe - will the 64bit WinObjEx64 still be ok to help us (you!) get to the bottom of this ?

I have sysinternals process monitor running on the machine. I get a long list of processes - but can't see my application mentioned anywhere (note - may application it is not actually doing anything at present - but it is still running) Any tips on how to drive this ?

I have remote access to the machine, My application is still running and I can confirm that it is still not able to create / write to any files. I have used the sysinternal handle.exe utility. When run with -a -p nnnn >MyOuptutTextFile.txt // (where nnnn = my application process ID) When I look at the resulting output file it is 400MB long and almost all of it is taken up with the same entries, here's an extract 3B4: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 3B8: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 // loads and loads and loads of entries here // - and then the file ends F71D78: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D7C: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D80: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D84: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D88: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D8C: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D90: <Unknown type> \Sessions\1\BaseNamedObjects\MyMutex1 F71D94: <Unknown type> \Sess This doesn't look healthy to me - but what does this line mean?

@Lajos Juhász How can I check this ?

Are you sure that "service" means a windows service in this context? I am not so sure that MS error messages are so precise! I think this just means a "general service provided by the operating system" - but I could be wrong. @Kas Ob. I am a bit out of my depth with this one - so your expertise is really welcome and appreciated. So above question is just me being ultra cautious!

When I open resource monitor I see 2 threads and 15 handle names (13 are files, one is the application exe and one is the application mutex created and checked by our application (we use this to prevent two instances being run at the same time) So this doesn't show any problem. Hard Disk still has 43GB used of a total capacity of 930GB

When I open up task manager I see 0% for CPU, disk and network, very low power useage and only 14.7MB of memory useage - and it's been running for a week and a half, so doesn't look like a memory leak.

An update: by adding code to get the Windows error code following a failed attempt to open a text file I have now got an error number : 1450 A quick google search reveals Error 1450 = Insufficient system resources exist to complete the requested service So what resources is it short of, I wonder? I am currently trying to get a remote connection to the PC in question before they close down (and restart) the application....

@JohnLM An interesting feature request. If you want it to be considered you need to post it at https://qp.embarcadero.com/ Helpful advice: Your suggestion (interesting though it is) is definitely well "off topic" so it might have been wise to post it as a new thread.

Well as a catch line it does make you want to attend the presentation.....