ThinkPad 770z - recovery CD problem

[Edward Mendelson]

Thanks to the generosity of theterminator93 on this forum, I have a recovery CD image for my TP 770z. I extracted the floppy image from the ISO and wrote the image to a diskette, and I burned the ISO (at 4X to improve my chances of getting a good disc). I booted the floppy from an external FDD (using the old battered machine that I mentioned in a previous message, and put the burned CD into the CD drive. When the floppy asked for a bootable recovery CD, I pressed enter, and the the program on the diskette told me, "This is a not a valid Recovery CD." I got the same result with a DVD drive and with a 24x CD drive.

Am I missing something obvious here?? Any help would be gratefully received.

[theterminator93]

Hm, that is strange. I've seen that when I tried using various boot floppy images when trying to get a 600 to restore that didn't match the CD it was looking for, but in this case, the image was pulled right from the CD.

I'm going to try rebuilding the ISO into a bootable format. I don't have a 770Z to try to boot to, but maybe my 770 will boot it, if it works? Obviously I won't be able to restore it, but if it boots, that is a step in the right direction. I'll let you know how it goes.

[Edward Mendelson]

I'm going to try rebuilding the ISO into a bootable format. I don't have a 770Z to try to boot to, but maybe my 770 will boot it, if it works? Obviously I won't be able to restore it, but if it boots, that is a step in the right direction. I'll let you know how it goes.

This is above and beyond the call of duty - thank you! I would guess that the CD would at least boot, and I can't figure out why the one I burned doesn't boot. The software I use (ImgBurn) is certainly able to make bootable CDs. Again, a thousand thanks for this!

[theterminator93]

Brief update before I pack things in for the night.

I did get it to start booting from the modified CD - it displayed "Starting Windows 95..." and the CD-ROM drive was seeking for a few seconds, but then the screen suddenly went black and the system rebooted. So I am not sure if this means the 770 can't boot to the 770Z restore CD, or if my attempt to get a bootable image failed... Sorry I can't be more help.

The only other things I can think of to try would be creating a Windows 95 boot floppy, overwriting all the contents with the contents of the 770Z image boot file to create a bootable floppy, then creating an image of that to try with my "create a bootable CD" method. That, and/or trying on a different model. Maybe I'll have better luck on my 600, so I can try it there next.

[Edward Mendelson]

Again, thanks for trying this. I think the CD disk should at least boot if it's bootable - it wouldn't boot when I tried booting from the CD drive, so something may be wrong with the ISO. I'll do some experimenting with this, and will also try booting on another machine.

[RealBlackStuff]

Have you tried an external CD/DVD via USB?

[Edward Mendelson]

Have you tried an external CD/DVD via USB?

Yes, the disk won't boot from an external CD/DVD either. (I did this on a different machine; the 770Z won't boot from USB.)

[NathanA]

How was the ISO made, precisely? Does theterminator93 actually own the original media, or did somebody else rip this?

If somebody can point me to a download link, I'd love to take a look at the ISO in question. Based on some of the other posts in other threads (weird filenames, etc.), my guess is that it was somehow made improperly.

If you're desperate, I note that Internet Archive has a couple of 770X recovery images available for download. I've seen eBay postings of 770Zs recently where the seller also included a picture of a 770X recovery CD sitting on top, implying that they used X recovery media to successfully re-image a Z, which makes some sense given how similar the X and Z are under-the-hood.

https://archive.org/download/LegacyThin ... ad%20770X/
https://archive.org/details/eyebeeyemfixedtheirgoof

The first one might be German. The second one says it has been "cracked" to ignore the machine type/model. I of course can't vouch for either.

I have an original 770 restore CD kicking around somewhere that I'd be happy to rip, but it's 1) Win95 and 2) likely not going to be as ideal as either an X or Z image, since the 770 was a P-MMX with 430TX chipset while both the X and Z were P-II with 440BX chipset.

[Edward Mendelson]

I found this link to a 770X recovery set on archive.org:

https://archive.org/download/LegacyThin ... ad%20770X/

I wrote the floppy and burned the CD, and started it up on my 770Z. Everything went well until it loaded the CD, and gave the error message "Error while unpacking compressed image".

Next, I realized that the CD is bootable, and when I booted from the CD, it successfully restored the 770x system - but the Windows 98 version it installed was the German-language one. (The recovery operation offered four languages, and I chose English, but the recovered system uses German.) This at least showed that the procedure works. So, if you want a German-language Windows 98 on a ThinkPad 770x or 770z, you can get it. English-speakers are still searching...

PS The download image may be the same as the German-language one listed in an earlier post. I haven't checked.

[Edward Mendelson]

Success: I was able to create a working 770z recovery CD by doing the following:

1. I started with the working German-language 770x recovery CD ISO on archive.org.

2. I used AnyBurn to remove the six IMZ files from the image.

3. I opened the non-booting 770z recovery CD image provided by theterminator93 and extracted the six IMZ files to a folder.

4. I renamed those six IMZ files to match the filenames of the IMZ files I removed in step 2.

5. I added those to the disk image that I was open in AnyBurn.

6. I saved the image to a new ISO and burned it.

When using it on a 770z, I got one "drive not ready error", but Retry worked, and the image was restored.

Here's the image for anyone who wants it:

https://mega.nz/file/wOhyjZgI#mfJyQzdb1 ... O3shOhapZc

[theterminator93]

Very clever, nice work!

I'll add this to my 770Z folder.

How was the ISO made, precisely? Does theterminator93 actually own the original media, or did somebody else rip this?

If somebody can point me to a download link, I'd love to take a look at the ISO in question. Based on some of the other posts in other threads (weird filenames, etc.), my guess is that it was somehow made improperly.

If you're desperate, I note that Internet Archive has a couple of 770X recovery images available for download. I've seen eBay postings of 770Zs recently where the seller also included a picture of a 770X recovery CD sitting on top, implying that they used X recovery media to successfully re-image a Z, which makes some sense given how similar the X and Z are under-the-hood.

https://archive.org/download/LegacyThin ... ad%20770X/
https://archive.org/details/eyebeeyemfixedtheirgoof

The first one might be German. The second one says it has been "cracked" to ignore the machine type/model. I of course can't vouch for either.

I have an original 770 restore CD kicking around somewhere that I'd be happy to rip, but it's 1) Win95 and 2) likely not going to be as ideal as either an X or Z image, since the 770 was a P-MMX with 430TX chipset while both the X and Z were P-II with 440BX chipset.

In my case, the 770* images I have were provided to me by other members. I have a stash of original recovery CDs for a couple dozen models but the 770 series is not among them, unfortunately - and while I do my best to maintain only known working recovery media images, since I don't known each model I have a set for, I can't test them all...

I do have a set for the 770, but I am not sure if it works. It's labeled 10L8564 and is 267 MB and I am not sure what OS it is for; it is bootable. If you're willing, I'd be curious if an ISO of your original restore media matches - if not, I'll keep it alongside the image I already have and test them on my 770 at some point.

[Edward Mendelson]

One detail:

During my experiments, I moved various boot images around, and got the 770z version of the recovery disk to work up to the point where it formatted the hard disk, but not any further. It starts up with completely different menus from the 770x recovery. it would be nice to get the original 770z image working if anyone can figure out to make it boot...

[theterminator93]

One detail:

During my experiments, I moved various boot images around, and got the 770z version of the recovery disk to work up to the point where it formatted the hard disk, but not any further. It starts up with completely different menus from the 770x recovery. it would be nice to get the original 770z image working if anyone can figure out to make it boot...

I've not given up completely, I do still plan to try and reconstruct the boot image. What I made the other day wouldn't boot on either my 770 with the P-MMX or 600 with the P-II. We'll see how this coming week at work pans out - sometimes I have motivation and time at the end of the day, other times, neither...

Bill had told me at one point he was going to send me all his old recovery CDs. He got as far as sorting them all into a box, but I haven't heard from him for a while. So, if that ever happens, I will be able to make images from the original source material for preservation and posterity.

[NathanA]

I do have a set for the 770, but I am not sure if it works. It's labeled 10L8564 and is 267 MB and I am not sure what OS it is for; it is bootable. If you're willing, I'd be curious if an ISO of your original restore media matches - if not, I'll keep it alongside the image I already have and test them on my 770 at some point.

I'll try to get around to digging it out of storage in the coming days & rip it for you.

My best guess about the story behind this 770Z image is that it wasn't a bit-for-bit rip of the media, but rather that whoever made it maybe copied all of the files off of it and then mastered a new ISO from that, or something. If you can link me to a URL to download a copy, I'd be interesting in dissecting it.

[NathanA]

My best guess about the story behind this 770Z image is that it wasn't a bit-for-bit rip of the media, but rather that whoever made it maybe copied all of the files off of it and then mastered a new ISO from that, or something. If you can link me to a URL to download a copy, I'd be interesting in dissecting it.

I have obtained a copy of this 770Z ISO from theterminator93, analyzed it, and think I can explain why it doesn't work.

It does indeed appear that my guess was correct: this ISO was remastered from scratch, rather than bit-for-bit ripped from the original media. (Argh. People need to learn how to use 'dd'. ) There's no smoking-gun here, just a lot of little tells that all add up.

This image is an ISO9660 filesystem with Joliet extensions. The last bit is important. Joliet is an extension to the standard ISO9660 CD-ROM filesystem that Microsoft introduced with Windows 95, in order to add support for things like DBCS/Unicode and long file names to CDs. It in essence adds a second file/directory listing to the CD for every file on the disc, in a place where most ISO9660 implementations will not look (and so won't be bothered/confused by it, for backwards-compatibility with systems that don't know how to interpret Joliet discs).

(UDF didn't exist until after Win95 was released. Even so, the *NIX world already had Rock Ridge extensions, but MS gotta MS... )

I don't know what software was used to master this image, but even though the disc contains no files with names longer than 8.3 characters, it's got a Joliet component to it, and the "correct" file names for each file are stored in there, while the names in the ISO9660 TOC are the weird ones without any file extensions (or where, if there was enough room within the first 8 characters, the extension was concatenated to the main file name with a '_' stuck in between, in place of the '.'). So "DFT.BAT" is called "DFT_BAT" in the ISO9660 listing, and "HKUSMA0.IMZ" turns into "HKUSMA08", etc. (so rules that are different than the normal VFAT long-to-short rules -- where you stuff a tilde '~' and a numeric suffix after the first 6 characters & before the extensions -- are being employed here by whatever CD mastering software was used).

Here's the thing: MSCDEX doesn't understand Joliet. There was no reason to ever update it to do so, since MS-DOS itself doesn't understand long file names. So if you mount this disc under Windows, you see the "right" names for each file. But under DOS, you see the wrong extension-less ones.

And of course, since IBM's image restore software is DOS-based and thus is dependent on MSCDEX to read the disc, and since it's going to be looking for *.IMZ files on this CD and not be able to find any, it bombs out.

As a comparison, I downloaded one of two 770 images that I found on archive.org (in this case, 05L1802). The 770 image has no Joliet extension component, properly-named files within the ISO9660 TOC, and is even bootable right out of the gate. This 770Z image also uses the IBM P/N as the filesystem volume label, while it appears IBM used some other kind of identifier for the volume labels on their official media.

To be clear, the problem isn't that this image has Joliet extensions included. That in-and-of-itself isn't a problem. It's that the file names within the non-Joliet part are wrong (the mastering software renamed them, and only kept the correct names within the Joliet file listings, which are not accessible under DOS). But there really is no point to having Joliet extensions on this image in the first place, since there are no non-ASCII or longer-than-8-dot-3 file names anywhere on the disc. Clearly somebody copied these files off the original 770Z disc, and then when they created this image, they just accepted whatever default settings their ISO mastering software was configured to use, which apparently for some reason involved unnecessarily renaming files that didn't need to be renamed...

The one thing I still can't explain is why the floppy boot image appears to be short by 33 sectors (1,457,664 bytes instead of 1,474,560). However, the BOOTIMG.BIN file on the 770 image I compared this to is the exact same size, so I'm guessing that it's not actually missing any data and that's just how it is...? Interestingly, 1457664 bytes is exactly how many bytes are free on a freshly-formatted FAT12 1.44MiB floppy diskette, and Microsoft explains the details behind this in this old KB article of theirs: the first sector is the MBR, then 9 sectors each for the redundant FATs, and then 14 sectors for the root directory. That said, I can mount this image under Windows with ImDisk just fine, & you'd think all of that would necessarily need to be present for that to be possible, which leads me to conclude that a chunk of empty space at the end of the diskette image were simply chopped off / omitted for some reason. Also, it's clear that BOOTIMG.BIN is what's being used as the image for El Torito boot here (given the presence of BOOTIMG.CAT, the El Torito Boot Catalog)...and though perhaps the MBR itself might not need to exist in that context, certainly you'd think that at least one copy of the FAT + the root directory itself would need to! (I'm going to have to read up on El Torito again...)

I do have a set for the 770, but I am not sure if it works. It's labeled 10L8564 and is 267 MB and I am not sure what OS it is for; it is bootable.

BTW, this (10L8564) is the same P/N that the second archive.org image I found bears...from the same repository as the 770X image that I pointed Edward at. I believe it is German-edition Win95. I'm going to guess/wager than when I unearth my own 770 restore discs, I'm going to find that their P/N matches the one I downloaded today for comparison (05L1802).

[NathanA]

I do have a set for the 770, but I am not sure if it works. It's labeled 10L8564 and is 267 MB and I am not sure what OS it is for; it is bootable. If you're willing, I'd be curious if an ISO of your original restore media matches - if not, I'll keep it alongside the image I already have and test them on my 770 at some point.

I'll try to get around to digging it out of storage in the coming days & rip it for you.

BTW, this (10L8564) is the same P/N that the second archive.org image I found bears...from the same repository as the 770X image that I pointed Edward at. I believe it is German-edition Win95. I'm going to guess/wager than when I unearth my own 770 restore discs, I'm going to find that their P/N matches the one I downloaded today for comparison (05L1802).

So, I finally got around to digging out my old 770 stuff this evening. The recovery CD in my case is actually P/N 06J0720, which I can't find any reference to on-line anywhere. The files are dated September 1997, and it is 338MB in size (compared to the German image's 267MB and the 05L1802's size of just over 300MB). The volume label of the 05L1802 image is EJUSFA0, while the volume label of mine is EGUSFA0. Mine did ship with a 9549-1AU, which came standard with the DVD drive, the MPEG2 hardware decoder daughterboard, and the DVD player software, so I'm wondering if maybe that's the difference between mine and the other English restore CD.

I'll try to get this ripped and posted next week sometime.

For the record, it looks like my 770 recovery set also included a "ThinkPad Recovery CD-ROM Boot Diskette", as well as a Microsoft Windows 95 OEM "Companion" CD.

[NathanA]

So, I finally got around to digging out my old 770 stuff this evening. The recovery CD in my case is actually P/N 06J0720 [...] and it is 338MB in size

[...]

I'll try to get this ripped and posted next week sometime.

I have made images of both the CD and the floppy boot disk, and sent theterminator93 links to them. Anybody else who is interested, just PM me...right now they're hosted on a low-bandwidth server, so I'm not keen on posting the URLs publicly for the time being.

Though Windows said the CD was only 338MiB in size, the rip I made is 389.5MiB (408384816 bytes). I'm not sure what the deal is with that extra 50MiB as I haven't had time to analyze the rip.