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unmapped memory exemption

keemun asked
Medium Priority
Last Modified: 2010-04-14
What is an "unmapped memory exemption"? What would this message indicate is wrong with the system? How can this be fixed?
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Edited text of question

More Info please....
OS, mac-model, Software, Hardware, When does it happen, What are you doing when it happens?


A friend of mine has been repeatedly crashing while printing from MiniCAD. He has a PC 7600/132 w/ 48 mgs, Mas OS8, Canon BJC-4550 w/ latest driver, and MC7.01. This past weekend, after weeks of reoccurring printing problems, I helped him do a clean reinstall of the system software and a complete reinstall of all his applications and files. We even installed a new printer cable. Things were working fine until I left...

He can print now but he is crashing in virtually every program and is getting an " unmapped memory exemption" message. Strange things are happening like the window for the "Find" command doesn't appear, and everything runs very slowly. He has run Norton Disk Doctor (3.5) and it doesn't report any problems. He has Conflict Catcher installed and it hasn't identified any conflicts, and he has Virex (latest version) in place which also hasn't found any viruses or problem files.

I have checked my resources and can't find any information regarding "unmapped memory exemptions". I have looked in "Sad Macs, Bombs and other Disasters" (3rd ed.) to no avail. I have done searches on  the MacFixIt and the Apple Technical Library web sites but don't turn up any information. (I know it must be in there somewhere!)

Thanks for providing the extra info. I can only say that.
1./ Your RAM could have gone bad.
2./ Conflict Catcher has been known to cause problems when used with "Extensions Manager", (Comes with OS7.5 and above, I think)
3./ It looks like things are OK right up to the last minute, (when you finish the install).
Before suspcting item 1, try....
What happens when you turn your extensions off?  Is your machine OK? if yes then try turning half of them ON, is it OK? if no, try turning off half of those that are open, off. If your mac is OK with the first half turned on, then turn ON half of the remainder. Keep using this process of elimination incase there is a conflict. The same goes for "Control Panels".

Knowing what the error means, will not show you what the problem is though.

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Thanks for your response. As indicated, I have installed the latest version of Virex which is supposed to deal with the Autostart Virus including the 3 or 4 variations. I have OS8.1 but was waiting a bit longer to install it until all the glitches were worked out with various other programs.(Don't want to add any more problems) I also have the latest Norton Utilities update but in their blurb they indicate that it is required only if you are using HFS+. It has been suggested that the erroors might be caused by bad RAM. Is this likley? Also I still haven't found out what exactly the error message refers to or means. Any info?

Currently, no version of Norton actually works to repair HFS+ volumes, so don't be duped by their erroneous claims that v3.5.2 (junk - works worse than 3.5.1) or higher is required. All v3.5.2 will do for you is tell you that it cannot fix HFS+ volumes. This is actually important in that it will not attempt to repair the HFS+ volume, which destroys the entire volume.

RAM does not usuall "go" bad. It is more likely that it is bad when you first put it in. You would get a sad mac at startup in that case.

I have never seen MacOS 8.0 run correctly on any machine. MacOS 8.1 has far fewer problems. Try using the LaserWriter8 driver with the correct printer description.

Let me know how you make out.


Update: Computer and printer taken in to shop. Apparently ran diagnostics and found no hardware problems with printer or processor ie RAM, processor, etc. Have talked with 3 people at Apple Canada and none of them have heard of this "unmapped memory exemption' error message.Is this possible??

Hi Keemun....
Did you have the virus that TheHub mentioned, I know we had it, and it is a bitch.
If your computer freezes, when you do a force quit, Sometimes it asks you if you want to quit from "Desktop Print Spooler".

Had you optimized your drive prior to this problem?
If so it may be exactly what it says. Since you move all the files on the drive some programs have trouble finding where you sent it to. The program attempts to look in the old location and that slot of memory is now unmapped. I had this problem and was worried it was a virus, but with patience I went through all the preference files and deleted them for each of the programs that were affected. Hopefully this works for you, good luck.
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