Check Demonstration data

Determine if the issue is software-related by checking if the issue occurs in Demonstration data.

• Demonstration data has no issues - continue to the Check existing known issues section
• Demonstration data has the same issues - uninstall and reinstall Sage 50 Accounts

Check the volume of data

There's no numerical limit to the number of transactions or records you can enter into Sage 50 Accounts. Your computer's disk space and memory limit the capacity. The following numbers are for guidance only. We can't give a specific limit as it depends on several factors including data size, network speed, number of concurrent users etc.

For optimal performance, we recommend:

• Fewer than 250,000 splits (transactions). This assumes that transactions are distributed evenly across all records within a specific module. For example, avoid posting 1,000,000 transactions to a single nominal code or customer record
• Fewer than 50,000 invoices
• Fewer than 50,000 sales orders
• Fewer than 50,000 purchase orders
• Fewer than 5,000 customer records
• Fewer than 5,000 supplier records
• Fewer than 20,000 product records
• Fewer than 2,000 project records

To check these, click Help then click About. The number of records appears in the Data Information section.

If you exceed the recommended number of transactions or records, reduce them below the recommended limits above. Delete old invoices and use the Clear Audit Trail option to remove old transactions.

If the amount of data isn't excessive or the problem persists, click Next.

Check that each computer meets the recommended system requirements and has the latest build of the software installed

• Further information about the system requirements
• Make sure you're using the latest build for your software version

If all Sage 50 Accounts computers meet the system requirements, have the latest build, and the issue persists, click Next.

Where is the issue?

Does the software run slow during one specific process or across all areas?

Software slow in one area

Reindexing a specific module can improve performance.

1. To take a backup of your data, in Sage 50 Accounts, click File then click Back up.
2. Click File then click Maintenance. If prompted to close any other windows, click Yes.
3. Click Reindex, select the affected module and click OK then Yes.
4. Click Compress Now and click Compress.
5. Click OK, Click Close and click Close again.

Software slow in all areas

Reindexing the relevant modules can improve performance.

1. To take a backup of your data, in Sage 50 Accounts, click File then click Back up.
2. Click File then click Maintenance. If prompted to close any other windows, click Yes.
3. Click Reindex, select the affected modules and click OK then Yes.
4. Click Compress Now and click Compress.
5. Click OK, Click Close and click Close again.

If Sage 50 Accounts is installed on a network, use a UNC path to access the data

Do this on every client computer using Sage 50 Accounts.

If you access the data on the server via a mapped network drive, change it to a UNC path. Locate your current data path in Help, then About, and note the data directory.

1. Browse to the Company file:

Version	Company file location
v31	C:\ProgramData\Sage\Accounts\2025
v30	C:\ProgramData\Sage\Accounts\2024
v29	C:\ProgramData\Sage\Accounts\2023
v28	C:\ProgramData\Sage\Accounts\2022
v27	C:\ProgramData\Sage\Accounts\2021
v26	C:\ProgramData\Sage\Accounts\2020

 

2. Double-click the Company file and choose Open with Notepad.
3. Update the paths in the Company file to the new server location. Use the relevant UNC path. For example, if your server's called Server and Sagedata is your shared folder, the UNC path is \\Server\Sagedata
4. Click File, click Save then click File and click Exit.

If the problem persists, click Next.

Check your data

Run the Check Data option to ensure data corruption isn't causing slow performance.

1. Open Sage Accounts and log into the affected company.
2. Click File, click Maintenance and then select Check Data.

Fix any errors before continuing. For further information, refer to our A - Z index of errors, warning and comments guide.

If you've multiple companies in Sage 50 Accounts, check each company separately.

If there are no errors in your data, click Next.

Check for .s50 files in Accdata

An excessive volume of .s50 files in the Accdata folder can cause performance issues. You can safely delete these temporary files.

1. Open your company data and click Help then About and select the Data Directory.
2. Delete any files with the extension .s50

File locking

Is there a dedicated server or computer on your network that centrally holds your data?

Check for file locking

If files remain open on your server computer longer than necessary, it can cause performance issues with Sage 50 Accounts.

 NOTE: Contact your local IT support for any help with these steps. 

To check if this is an issue:

1. In your Windows Search bar, type Computer Management.
2. On the Computer Management window, open Shared Folders then select Open Files.

This lists all the files open on your server including Sage 50 Accounts data files.

The system automatically removes the Sage data files displayed within Open Files. The removal time varies based on your setup and other software.

When the files close, click Next.

Antivirus software and scheduled tasks

Modify your antivirus software to work with Sage Accounts to prevent conflicts.

 NOTE: Speak to your local IT support before you change your antivirus or scheduled tasks. 

If the issue occurs at specific times of the day or days of the week, adjust your scheduled tasks where needed:

• In your Windows Search bar, type Task Scheduler

Sage user-specific issues

Log in as a different Sage user to recreate performance issues.

1. Click File then click Log Off.
2. Enter a different logon.
3. Recreate the process that caused the performance issue.

If you're using the Manager logon, recreate the performance issues as a standard user.

 TIP: If you need to create a new logon, click Settings, then User Management, then Users and select New. 

Does the problem happen when using a different Sage logon?

Windows user-specific issues

Try to recreate the performance issues using a different Windows user.

Does the problem happen when using a different Windows logon?

 NOTE: If you've only one Windows logon, select Yes.  

Fixing Sage user-specific issues

1. Delete their username files in the Criteria folder and any user files in the Accdata folder.
2. Reopen Sage Accounts and recreate the issue.
3. If the issues persist, create a new Sage username for the affected user.
4. Click File then Log Off, then enter the new username.
5. Recreate the performance issues.

If the performance issues persist, click Next.

Fixing Windows user-specific issues

If the issue occurs for specific Windows users, speak to your local IT support. They can use the checking environmental issues guide from our Help Centre to troubleshoot the problem.

Test the network transfer speed outside of Sage 50 Accounts

To do this, copy the Reports folder from the client computer to the shared folder on the server computer. Then time how long it takes to complete.

The standard location for the Reports folder is:

Version	Reports folder location
v31	C:\ProgramData\Sage\Accounts\2025\Company.000
v30	C:\ProgramData\Sage\Accounts\2024\Company.000
v29	C:\ProgramData\Sage\Accounts\2023\Company.000
v28	C:\ProgramData\Sage\Accounts\2022\Company.000
v27	C:\ProgramData\Sage\Accounts\2021\Company.000
v26	C:\ProgramData\Sage\Accounts\2020\Company.000

 

1. On the client PC, open Sage Accounts.
2. Click Help, then About. In the Program Details area, note of the Data Directory.
3. Hold down the Windows key and press E to open File Explorer, then browse to the Reports folder.
4. Right-click the folder and select Copy.
5. Browse to the route of the local disk on the server, click Edit, then click Paste.
6. Time how long it takes to complete the process.
7. Repeat steps 4 and 5 two more times and calculate the average time taken. Because the first transfer can take longer, take the average of the second and third file transfers.

On a 100 Mbps network, the folder transfers in 30 - 40 seconds. On a 1 Gbps network, the folder transfers in 15 - 20 seconds.

8. Repeat the process and time the transfer from the server back to the client computer.

If the file transfer exceeds 80 seconds on a 100 Mbps network or 40 seconds on a 1 Gbps network, it suggests performance issues. Until network speed improves, your software will remain slow. For further advice on the cause and resolution, consult your network administrator.

If the network transfer speed is OK, click Next.

Relocate your data to a new location

1. Move your Sage 50 Accounts data to a different server location to check if the issue persists.
2. Open Sage 50 Accounts and recreate the issue.

If the problem persists, undo the changes made to the Company file then click Next.

Further investigation

If you require further help with this, to find the best way to contact us visit our Help Centre.