TallyPrime Upgrade Checklist: Keep Your TDL Add-ons Working
Before you update TallyPrime to a new release, check your TDL add-ons, take a backup and test on a copy. A step-by-step upgrade checklist.
Upgrading TallyPrime to a new release usually brings useful features, but it can also change how TDL add-ons behave. A report that printed perfectly yesterday may show an error after the update, or a custom field may disappear from the voucher screen. This TallyPrime upgrade checklist helps you keep your TDL add-ons working by checking compatibility before you update, not after.
Why TDL compatibility matters during an upgrade
A TDL (Tally Definition Language) file changes TallyPrime's screens, reports or print formats. It is written and tested against particular TallyPrime releases. When Tally changes a screen or report in a new release, an add-on that modifies the same area may need an update. Many add-ons keep working without changes, but you only find out which is which by checking.
Tally Solutions publishes a guide on moving from older TallyPrime releases to the latest one. Read it alongside this checklist, because some releases also ask you to migrate company data.
Before you upgrade: the checklist
- Note your current release. Open F1: Help > About and write down the release number.
- List every TDL you use. Press Ctrl+Alt+T to open TDL Management and take a screenshot of the list, including file paths.
- Ask each developer about the new release. Give them the add-on name and the release you plan to install, and ask whether an updated file is needed.
- Take a full backup. Back up company data and copy your TDL folder. If backups are not automatic yet, see how to set up automatic backups in TallyPrime.
- Check your licence. Make sure your licence covers the new release. Our TallyPrime licensing page covers plans if you need to renew or change editions.
- Pick a quiet time. Avoid the days before GST filing or month-end closing.
Test on a copy before you switch everyone
The safest upgrade is a rehearsal. Install the new release on one computer, restore a copy of your company data there, and load your TDLs. Then work through the screens your team uses every day:
- Create and print a sales invoice with each custom print format.
- Open every custom report and compare totals with the old release.
- Enter one voucher of each type that has custom fields.
- Confirm that TDL Management shows every add-on as loaded.
If something fails, you have lost nothing: your live company is still on the old release while the developer prepares a fix.
Rolling out the new release
Once the test passes, upgrade the remaining computers. In a multi-user office, keep every computer on the same release, because an add-on can behave differently between releases. If a developer sent you an updated TDL, replace the old file in your TDL folder and re-check TDL Management on each computer. Our guide to installing a TDL in TallyPrime covers loading and verifying the file.
If a TDL stops working after the upgrade
| What you see | What to do |
|---|---|
| The add-on is listed but not loaded | Check the file path in F4: Manage Local TDLs, then ask the developer whether the file supports the new release |
| A custom report shows an error | Send the developer a screenshot and your release number from F1: Help > About |
| A print format looks broken | Print the same invoice on the test copy of the old release to confirm the change came from the upgrade |
| Daily work is blocked | Go back to the previous release and your backup until an updated add-on is ready |
Make the next upgrade easier
Keep a simple register of your add-ons: name, supplier, file location and the releases it was tested on. When you buy new add-ons, check the supported release on the product page first. Browse TallyPrime add-ons with that in mind, and if an add-on you rely on is no longer maintained, our Tally customization team can review whether it should be rebuilt for your current release.
Frequently asked questions
Will my TDL add-ons work after I upgrade TallyPrime?
Often they do, but it is not guaranteed. A TDL is built and tested against particular releases, so confirm with the developer that your add-on supports the release you are moving to before you upgrade.
How do I check which TallyPrime release I am using?
Open F1: Help > About. The About screen shows your TallyPrime release, which you need when asking a developer about add-on compatibility.
What should I do if a TDL stops working after an update?
Note the exact error and your new release number, then contact the add-on developer for an updated build. If the issue blocks daily work, restore the previous release and your backup until the fix is ready.