Troubleshooting (Top 20 issues)

A collection of the 20 most common problems plus detailed fixes, grouped by feature area.

Installation

#1 — "It was not possible to find a compatible framework version for .NET Desktop Runtime"

Cause: the .NET 8 Desktop Runtime is not installed in the bitness that matches Excel (not the bitness of Windows).

Fix:

1. Open Settings → Apps → Installed apps.
2. Look for "Microsoft Windows Desktop Runtime - 8.0.x".
3. If only (x86) is present but Excel is 64-bit → install the x64 runtime as well, and vice versa.
4. Manual download:
   • x64: windowsdesktop-runtime-8.0.11-win-x64.exe
   • x86: windowsdesktop-runtime-8.0.11-win-x86.exe

#2 — The DVD Addin / DVD Cons tab does not appear on the Ribbon

Cause: Excel has not loaded the add-in (the OPEN key was deleted, or Excel disabled the add-in after a crash).

Fix:

1. File → Options → Add-ins → Manage = Excel Add-ins → Go.
2. Tick DVDAddin-AddIn64-packed.xll.
3. If it is not in the list → Browse → select:
   • 64-bit: C:\DVDAddin\DVDAddin-AddIn64-packed.xll
   • 32-bit: C:\DVDAddin\DVDAddin-AddIn-packed.xll
4. Still nothing → File → Options → Add-ins → Manage = Disabled Items → Go → remove the add-in from the disabled list.

When it is installed correctly you see two tabs: DVD Addin and DVD Cons.

#3 — Installed the new build but the old bug is still there / it is still the old version

Cause: Excel keeps the .xll file in memory for the whole session. If any Excel window was open during the installation, the old build is still sitting in RAM (and the installer may not have been able to overwrite the file).

Fix:

1. Close ALL Excel windows — check the EXCEL.EXE process in Task Manager and kill any leftovers.
2. Close Outlook too (Outlook can start Excel in the background to preview attachments).
3. Run the installer again.
4. Open Excel → DVD Addin → About → compare the version number shown with the build you just installed.

This is the number one cause of the "it was fixed but the bug is still there" situation.

License

#4 — "No active license for this account"

Cause: the account has no valid license — it expired, was revoked, or the order has not been recorded as paid.

Fix:

• Open DVD Addin → License and read the status card at the top of the dialog: the current plan and its expiry date are there.
• Expired → use Buy License to renew.
• Just paid but no key yet → check your inbox (including spam); the transfer memo must keep exactly the string the dialog generated, because editing it stops the system from matching the transaction.

#5 — "Invalid credentials" when signing in

Cause: wrong email/password, or the account is locked.

Fix:

• Type the email correctly, with no extra spaces (the email box accepts up to 200 characters).
• If you changed your password after the first sign-in, use the NEW password, not the temporary one from the email.
• Forgot the password → contact the Zalo support group so an admin can reset it.

#6 — Just activated, but commands still say a license is required

Cause: the ribbon is still holding the old license state of the running Excel session.

Fix:

• Close the License dialog — in most cases the ribbon refreshes by itself.
• If it is still locked → close Excel completely and reopen it.

#7 — Working normally, then it reports the license expired / disappeared

Common causes:

• Offline for too long. The add-in holds a session token valid for 7 days plus about 1 day of buffer — roughly 8 days of offline use from the last online check.
• The session was kicked. The account has just signed in on another machine; each license allows only one active session at a time.
• The machine clock was moved backwards. The add-in records the highest timestamp it has ever seen; if the system clock falls more than 1 hour behind that mark, the session is treated as invalid and the offline buffer window is wiped as well — setting the clock back to the correct time does not restore it automatically, so you must go online and sign in once more. The 1-hour threshold leaves room for small NTP drift, daylight saving changes, and virtual machines that have just resumed.

Fix: turn on automatic time synchronisation in Windows (Settings → Time & language → Set time automatically), then go online → open License → sign in again.

#8 — "Access denied" when saving the license state

Cause: the file %LocalAppData%\DVDAddin\license.dat is set read-only, or the whole folder is write-protected (ACL, Windows Defender's Controlled Folder Access, a leftover old folder).

Fix:

1. Open %LocalAppData%\DVDAddin → clear the Read-only attribute on license.dat, or delete the file entirely (the add-in recreates it at sign-in).
2. If the error persists → delete the whole %LocalAppData%\DVDAddin folder and sign in again.
3. Check whether Controlled Folder Access in Windows Security is blocking Excel from writing to that folder.

The add-in also keeps a copy of the license in the HKCU registry, so you usually do not lose the session while doing this.

Translation & AI

#9 — Gemini reports "output blocked (SAFETY / RECITATION)"

Cause: that is a finishReason returned by Gemini itself, not an add-in error.

Fix:

• RECITATION — the content matches published material (standards, contract clauses). Split the range being translated into smaller pieces or rephrase it.
• SAFETY — switch to Google or ChatGPT.
• MAX_TOKENS — the selection is too large for the model; split it up or pick a model with a larger context window.

#10 — Asked for the "API key" again / error 401 Unauthorized

Cause: no key has been entered for the provider currently selected, or the key is wrong/revoked.

Fix:

• Go to Preferences → the AI Assistant section → enter the key for the exact service set as the Service. A Gemini key does not work when the Service is Groq.
• Get a new key:
  • Gemini: aistudio.google.com/apikey
  • ChatGPT: platform.openai.com/api-keys
  • Groq: console.groq.com/keys
  • NVIDIA NIM: build.nvidia.com

#11 — Gemini reports "quota exceeded"

Cause: you have exceeded the Google AI Studio free tier limit for your key.

Fix:

• Wait for the limit window to reset.
• Switch the Service to Groq or NVIDIA (a different free tier).
• Reduce the load: the selection is split into batches of 25 cells and up to 10 batches run in parallel — translating in smaller waves hits the per-minute limit less often.

#12 — The translate command returns an error even though the network is fine

Fix:

• Check whether the company firewall/proxy is blocking generativelanguage.googleapis.com, api.openai.com, api.groq.com.
• Try Google first — that service needs no API key, so if Google works the problem is with the key/provider rather than the network.

Printing & Export

#13 — Batch print takes a very long time or looks like Excel has frozen

Cause: on every iteration the add-in writes a number into the driver cell and lets Excel recalculate the whole sheet — with hundreds of iterations, a few minutes is normal. Unusually slow runs are usually caused by the workbook's VBA.

Fix:

• If the workbook has a Worksheet_Change, add Application.EnableEvents = False at the start of the handler, or move the form into a workbook without VBA.
• Do not type into any cell while the command is running — Excel will reject the add-in's COM operations.
• Save the workbook before a large batch: the driver cell has its real value overwritten during the run.

#14 — Merge to Word produces empty files / does not replace the placeholders

Cause: the placeholders do not match the column headers.

Fix:

• Write placeholders as [TenCot] (square brackets) matching the column header EXACTLY, including Vietnamese diacritics and spaces:

  ✗ [Hang muc]   → column header is "HangMuc" → NO match
  ✗ [ HangMuc ]  → extra spaces → NO match
  ✓ [HangMuc]    → correct

• The data range must INCLUDE the header row.
• Placeholders inside the header / footer / text boxes of the template file may not be replaced — move them into the body of the document.
• The column chosen for the file name must contain unique values, otherwise the output files overwrite each other.

#15 — The exported PDF has extra blank pages

Cause: automatically inserted page breaks, or empty dvdPic picture areas still being printed.

Fix: in the Options frame of Batch print:

• Turn off auto-insert a page break at the signature block if the form already fits the page.
• Turn on both options to skip picture areas / print areas that have a dvdPic formula but no image.

#16 — Send Email does not run / gets marked as spam

Cause: the command sends mail through Outlook on the machine; it does not talk to a mail server directly.

Fix:

• Microsoft Outlook must be installed on the machine with an account already configured.
• Always click Preview for the first iteration to see the message open in Outlook before clicking Send — sent mail cannot be recalled.
• Avoid sending hundreds of messages with an identical subject and body; the recipients' mail filters will mark them as spam.
• Attachment paths must exist on the machine; for several paths in one cell, put one path per line (Alt+Enter).

DVD Cons (Construction)

#17 — The Gantt chart is drawn but the dates are wrong

Fix:

• Start / Finish must be in Date format, not Text.
• Predecessors must use the Activity ID + relationship type (MHC1060FS, MHC1090SS, MHC1150FF).
• Duration must be a whole number of days.
• Turn on Auto Calc; also turn on Auto Draw if you want the chart to update itself.
• Check the working calendar and the non-working days in Setup and in the Input sheet of the template file.
• Do not click a command while the cursor is blinking inside a cell (in-cell edit mode).

#18 — Rebar cutting produces a high scrap rate

Fix:

• Check the saw kerf entered per diameter/steel grade — the default is 4 mm.
• The Cho phép nối (Yes/No) (allow splicing) column in the 02_NhuCauCat sheet: setting No for pieces almost as long as the 11.7 m stock bar always produces large offcuts.
• Enter the remnant stock so the algorithm can reuse part-used bars.
• The Rebar cutting preview window lets you click Close to cancel completely — no sheet is written, so try as many options as you like.
• After Apply, the result sheets are overwritten and Ctrl+Z will not restore them.

#19 — Connect: clicking the command does nothing / cannot synchronise

Causes & fixes:

• The window does not open — the license has expired or you have not signed in. The command shows no error message; it simply does not open.
• The host has not set an Admin password — the add-in warns "Host must set Admin password!" and does not start the server.
• Data arrives but cannot be read — the Data password encrypts the packets, and every machine in the session must type it identically.
• Cannot connect over LAN — the machines must be on the same subnet, and the port (default 8888) must be open in the Windows firewall on the host machine.
• Closing the window does not end the session — to leave completely you must use the Disconnect command.

Workbook & Performance

#20 — The workbook is slow after installing DVDAddin

Cause: volatile functions recalculate on every Excel recalc: dvdAutoHide, dvdMCLookup, dvdMVLookup, dvdSumVisible, dvdUniqueV. The four network functions (dvdTranslate, dvdStock, DVDFx, dvdAIExplain) are even heavier when filled down many rows.

Fix:

• Limit the number of cells using volatile functions; in many cases dvdXlookup or SUBTOTAL can replace them.
• Once the figures are final, convert them to static values (Ctrl+C → Paste Special → Values).
• Switch Excel to Manual calculation while editing a large table.

Diagnostic checklist

When you hit an error with no obvious cause:

1. Close Excel completely (check EXCEL.EXE in Task Manager) → reopen → try the command again. A great many "strange" errors are just the old add-in still in memory.
2. Update to the latest build — DVD Addin → About Menu → Check Update.
3. Restart Windows — this resets the COM state.
4. Check the on-disk data:
   • %LocalAppData%\DVDAddin\license.dat — the license state.
   • HKCU\Software\DVD\DVDAddin\ — all the settings (Preferences, API Keys, Model, Service, GanttSettings…).
   • C:\DVDAddin\Template\ — the 6 template files; if this folder is missing, the template commands fail with an error listing the paths they searched.
5. Look at the logs (if support asks for them):
   • %TEMP%\DVDAddin\ — the watchdog log and some command logs.
   • %TEMP%\dvdaddin-chat.log — DVD Chat.
   • %TEMP%\DVDAddin_Sync_Log.txt — Connect.
   • %LocalAppData%\CrashDumps\EXCEL.EXE.*.dmp — dumps from an Excel crash.
6. Rule out add-in conflicts: File → Options → Add-ins → untick the other add-ins one at a time and retest with DVDAddin alone.
7. Try it on another machine to separate a product bug from a machine configuration problem.

Reporting bugs

Report through the Zalo support group (zalo.me/g/yqzwvk121) or a GitHub Issue (github.com/dangdvd/DVDAddin/issues), including:

• The add-in version number — open DVD Addin → About and take a screenshot (the window shows both the version and the license type).
• The Excel version (32/64-bit) + Windows version.
• A description of the error + the steps to reproduce it.
• Log files if you have them.
• A screenshot for any UI problem.

Related

• FAQ — frequently asked questions.
• Installation — installation in detail.
• License — the license in detail.
• Full command reference — every command and every field in its dialog described.