I am running Windows 95 on a system comprising a Pentium 166 processor.
I have had the system for 2 years without problems.
PROBLEM
Initially I get a message" Windows has encountered a Registry problem, please restart". Unfortunately, when I try to restart it freezes on the first windows screen.
I have tried "Safe mode" but I get the message"Himem.sys has detected unreliable XMS memory at address 00142228. XMS driver not installed".
When I try to continue it says "Himem. sys is missing" (it's not!!)and trys to reboot.
If I go through "step by step" I load himem.sys, it then asks to load the XMS driver. If I load it it crashes. If i say no, I can generally load everything else (sometimes loading IFSLP? also causes it to lock up).
When I get to WIN it tries to load the drivers and locks up immediatly.

I have checked HIMEM.SYS is ok and present.
Occasionally, If I have switched everything off from the mains for a few hours it will start up. Then it will run non stop for weeks before it all starts again.
The last time it did it I reloaded Windows95 and although it didn't start the first time, after leaving it for a while it started up but only in 16 colour(with no option to change it in "settings").
I have spent hours trying to get the darn thing running. Can anyone please help before I sling the whole thing at the wall!!!

Mike

Sorry, I saw this one a few days ago, late at night, and was to dingy and thought I'd wait till later...it's later than I intended...

Boot to a win95 start up disk, and find the registry files. They will be named user.dat and system.dat. Rename them, using a different extension you'll recognize. Example:

C:\>ren user.dat user.bad would rename user.dat to something you know is the bad one. Your initials would work too. Remember the spaces, they have to be there.

Then look for backup copies, they'll be user.da0 and system.da0 or user.bak and system.bak. Check dates, and rename the ones you want user.dat and system.dat. Look for a date that was before the problem started. the .da0 files are the original backups made when windows was installed, or the first time you installed more software, I can't remember which.

After renaming the files, reboot and see if it works ok. Since you're effectively resetting everything back to a previous state, you might have to reinstall some programs, since the registry no longer knows they're there.

Be careful doing this, and pay close attention to what you're doing. If you're not absolutely sure about it, ask a friend who knows his/her way around DOS to help you. Write down everything you do.

Check my site, posted below, and you'll find a couple of very good links to DOS help, and some troubleshooting sites, plus other good info you might find helpful.

Let's hope it works and you don't have to format/reinstall...

The unreliable memory message might be a whole 'nother problem, let's see if we can get it to boot, then deal with memory. Once you rename the registry files if it still gives you the memory error, check and see how many chips you have. You might be able to remove half and see if you can swap from one to another and find the bad chip(s). Also try reseating the memory chips, they might just have bad contact. Clean the contact pins with a red rubber pencil eraser. Make sure to ground yourself on a bare metal area of the case before touching anything inside. Static electricity can damage internal components very easily. It takes 2,000 volts for you to feel it, only 100 volts will blow computer cards. You can create 200-300 volts just turning in your chair. Keep an elbow on the case while handling parts, cleaning contacts, etc.

------------------
If you had everything...Where would you put it?

Computer Information Links (http://www.geocities.com/paleopete/)

Originally posted by Mike Sturla:
I am running Windows 95 on a system comprising a Pentium 166 processor.
I have had the system for 2 years without problems.
PROBLEM
Initially I get a message" Windows has encountered a Registry problem, please restart". Unfortunately, when I try to restart it freezes on the first windows screen.
I have tried "Safe mode" but I get the message"Himem.sys has detected unreliable XMS memory at address 00142228. XMS driver not installed".
When I try to continue it says "Himem. sys is missing" (it's not!!)and trys to reboot.
If I go through "step by step" I load himem.sys, it then asks to load the XMS driver. If I load it it crashes. If i say no, I can generally load everything else (sometimes loading IFSLP? also causes it to lock up).
When I get to WIN it tries to load the drivers and locks up immediatly.

I have checked HIMEM.SYS is ok and present.
Occasionally, If I have switched everything off from the mains for a few hours it will start up. Then it will run non stop for weeks before it all starts again.
The last time it did it I reloaded Windows95 and although it didn't start the first time, after leaving it for a while it started up but only in 16 colour(with no option to change it in "settings").
I have spent hours trying to get the darn thing running. Can anyone please help before I sling the whole thing at the wall!!!

Mike

Thanks for the help Pete, I finally got to the bottom of it.
What was happening was that there was a fault in one of the Ram chips.
Apparently HIMEM.sys does a check to each memory address and looks for the same data to be returned. If it gets the wrong reply it gives the error message and WILL NOT LOAD itself. Therefore when trying to load windows
it looks for HIMEM.SYS cant find it and locks out.
I have changed the faulty chip and everything is A OK!!
Mike

Thanks for the help Pete, I finally got to the bottom of it.
What was happening was that there was a fault in one of the Ram chips.
Apparently HIMEM.sys does a check to each memory address and looks for the same data to be returned. If it gets the wrong reply it gives the error message and WILL NOT LOAD itself. Therefore when trying to load windows
it looks for HIMEM.SYS cant find it and locks out.
I have changed the faulty chip and everything is A OK!!
Mike