docs: Update dataforth-dos session log

Session log updates for 2026-01-20 with additional work documentation.

This checkpoint also marks completion of GuruRMM security remediation:
- Phase 1: 10 critical security fixes deployed
- Phase 2: 8 major fixes deployed
- Production server updated at 172.16.3.30
- Gitea tracking issue #1 updated

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

projects/dataforth-dos/session-logs/2026-01-20-session.md

@@ -324,3 +324,81 @@ See PROJECT_INDEX.md for complete project reference.
 
 **Status:** COMPLETE - Ready for production testing
 **Next Session:** Monitor TS-4R results, prepare for full rollout
+
+---
+
+## Session Continuation (18:00)
+
+### Additional Fixes Applied
+
+After initial testing on TS-4R and TS-3R, two more DOS 6.22 compatibility issues were discovered and fixed:
+
+**Issue 1: "Too many parameters - 2" error**
+- Cause: `2>NUL` stderr redirection not supported in DOS 6.22
+- Solution: Removed all `2>NUL` from MD commands, use only `>NUL`
+- Files affected: CTONW.BAT, NWTOC.BAT, DEPLOY.BAT
+
+**Issue 2: "Invalid number of parameters" on XCOPY**
+- Cause: XCOPY needs `/I` flag to assume destination is directory
+- Solution: Added `/I` flag to all XCOPY commands
+- Files affected: CTONW.BAT, NWTOC.BAT
+
+**Issue 3: AUTOEXEC.BAT missing startup commands**
+- Request: Add CD \ATE and menux to generated AUTOEXEC.BAT
+- Solution: DEPLOY.BAT now appends CD \ATE and menux after "System Ready"
+
+### Files Updated (This Session)
+
+| File | Version | Changes |
+|------|---------|---------|
+| CTONW.BAT | v2.5 | Removed 2>NUL, added /I to XCOPY |
+| NWTOC.BAT | v2.8 | Removed 2>NUL, added /I to XCOPY |
+| DEPLOY.BAT | v2.3 | Removed 2>NUL, added CD \ATE + menux |
+
+### Deployments
+
+1. Fixed CRLF line endings (files had CR CR LF, corrected to CR LF)
+2. Deployed to AD2: `C:\dataforth\test\COMMON\ProdSW\`
+3. Deployed to NAS: `/data/test/COMMON/ProdSW/`
+4. Cleared all machine-specific ProdSW folders (64 folders on NAS)
+5. Created TEST.BAT on NAS for sync verification tomorrow
+
+### Testing Results
+
+- **TS-4R:** [OK] Deployment successful, no errors
+- **TS-3R:** [OK] Deployment successful, no errors
+
+### Infrastructure Updates
+
+**Added SSH key to NAS:**
+```bash
+ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDrGbr4EwvQ4P3ZtyZW3ZKkuDQOMbqyAQUul2+JE4K4S azcomputerguru@local
+```
+Added to `/root/.ssh/authorized_keys` on D2TESTNAS (192.168.0.9)
+
+### Git Commits
+
+1. `d979fd8` - fix: DOS 6.22 batch file compatibility - XCOPY /Y and simplified scripts
+2. `6d3271c` - fix: DOS 6.22 compatibility - remove 2>NUL, add XCOPY /I flag
+
+### DOS 6.22 Lessons Learned (Updated)
+
+**Additional incompatibilities discovered:**
+- `2>NUL` (stderr redirection) - NOT supported, use `>NUL` only
+- XCOPY without `/I` flag - may prompt for F/D destination type
+
+**Working commands:**
+- `MD dir >NUL` - Ignores "directory exists" errors
+- `XCOPY source dest /Y /I >NUL` - Unattended copy, assume directory
+
+### Pending Verification
+
+- TEST.BAT placed in T:\COMMON\ProdSW on NAS
+- Should appear in C:\BAT on DOS machines after next boot
+- User will verify sync tomorrow
+
+---
+
+**Session End:** 2026-01-20 18:10
+**Total Duration:** ~8 hours (including continuation)
+**Final Status:** All issues resolved, tested successfully on TS-4R and TS-3R