Author Archives: Michal Necasek

DOS 4.0, bum rap, and mismatched expectations

Posted on April 15, 2012 by Michal Necasek

While researching the history of DOS extenders, I came across an article written in 1991 and explaining why OS/2 2.0 was going to be horribly incompatible with Windows 3.x. To support the argument, the following statement was used: “When IBM … Continue reading →

Posted in IBM, PC press | 13 Comments

NetWare for OS/2

Posted on April 13, 2012 by Michal Necasek

NetWare for OS/2 was one of the most technically interesting products of the mid-1990s. Novell’s NetWare was long established as a file server for LANs; since NetWare/386, Novell’s NOS ran as a dedicated server which was loaded from DOS but … Continue reading →

Posted in NetWare, Networking, OS/2 | 4 Comments

From a Feature to a Bug

Posted on April 6, 2012 by Michal Necasek

Sometimes the quest for backwards compatibility has unintended consequences. In some cases, the presumably beneficial backwards compatibility turns into a source of problems. The costs end up far outweighing the benefits, yet the “feature” may be difficult to get rid … Continue reading →

Posted in DOS, PC history, Windows | 13 Comments

Operating System/2 announced 25 years ago

Posted on April 1, 2012 by Michal Necasek

On April 2nd of 1987 (not April 1st, that wouldn’t do!), IBM and Microsoft jointly announced Operating System/2, the long-awaited protected-mode version of DOS. However, OS/2 was not the only product announced on that day. OS/2 was merely one part … Continue reading →

Posted in IBM, Microsoft, OS/2, PC history | 27 Comments

64-bit trouble with Solaris 10 U4 and earlier

Posted on March 26, 2012 by Michal Necasek

On many newer systems, Solaris 10 releases up to and including Solaris 10 8/07 (that is Update 4, also known as S10U4) behave in an unhelpful manner. The installer can be launched from CD or DVD and the system can be … Continue reading →

Posted in Solaris, x86 | 12 Comments

Video trouble with Solaris 10 GA and U1

Posted on March 23, 2012 by Michal Necasek

The initial (GA) release of Solaris 10 from 2005 and the first update (Solaris 10 1/06) both have an interesting bug which causes trouble when installing those specific versions on VirtualBox and quite likely also on some mildly unusual hardware. The … Continue reading →

Posted in Solaris, VirtualBox | Leave a comment

Lotus 1-2-3 R3 copy protection

Posted on March 17, 2012 by Michal Necasek

Release 3 of Lotus 1-2-3 (1989) utilized a mild form of copy protection which relied partially on technology but primarily on shaming would-be pirates. 1-2-3 installed from copied disks prominently showed the name of the original owner every time the … Continue reading →

Posted in DOS, OS/2, PC history | 9 Comments

NT video miniport HD

Posted on March 9, 2012 by Michal Necasek

The video miniport driver for VirtualBox has been updated. The miniport now supports a much broader range of resolutions, up to 1920×1200. Color depths of 32, 24, 16, 15, and 8 bits per pixel are supported for all resolutions, although … Continue reading →

Posted in NT, VirtualBox | 23 Comments

AVX support disrupts WoW64 debugging

Posted on February 29, 2012 by Michal Necasek

Sometimes, the old and the new intersect in unexpected ways. After upgrading to a Sandy Bridge based system (Core i7) and Windows 7 SP1 64-bit some time ago, I noticed that debugging exceptions in 32-bit user programs didn’t quite work … Continue reading →

Posted in Windows, x86 | 18 Comments

LAN Manager vs. Windows 7

Posted on February 26, 2012 by Michal Necasek

I recently spent some time trying to access disks shared by a Windows 7 machine from various versions of OS/2 (running in VMs, although that’s not really relevant). The OS/2 clients ranged from OS/2 1.3 with LAN Manager 2.1 (1991 … Continue reading →

Posted in Networking, OS/2, Windows | 28 Comments