FLEXlm Network License Error -15 Troubleshooter
Solve the most common online errors in CAD online version. Interactive boot, PowerShell script one-click diagnosis and configuration generation, 100% Run locally to protect privacy.
Network permission link topology monitoring
Network Licensing Link Path Topology
Diagnostic process progress
Server parameter settings
Step 1: Select your failure scenario
Recommend corresponding troubleshooting entry points based on specific fault symptoms.
FLEXlm Online version -15 Depth error reporting principles and troubleshooting knowledge base
FLEXlm Error -15 In-depth Technical Principles & Solution Hub
Why do both ports trigger -15 errors?
Many network administrators deploy CAD floating servers, I habitually only open the service port of `lmgrd.exe` in the firewall. (Usually 27000). When the client initiates a connection, the main process will respond to the client with a randomly selected Vendor supplier process. (For example, the port of `adskflex.exe`). Because the port is blocked by the server firewall, the client eventually generates a handshake timeout. Returns `Error -15: Cannot connect to license server`. Therefore, Locking the Vendor port is the first step to ensure stability.
Why hostname/DNS resolution is the first step in troubleshooting?
CAD The client starts up and queries environment variables such as `ADSKFLEX_LICENSE_FILE=@my-server`) When, first call the operating system's DNS Parse the module to obtain the intranet of `my-server` IP. If WINS/DNS services are not deployed on the network, or the client cannot find the corresponding record in the host Hosts, the connection will be interrupted directly during the domain name resolution stage. If such a failure occurs, using IP directly is often the fastest temporary alternative.
Client environment variable priority principle
In Windows environment, FLEXlm Reading the licensing configuration follows a specific order: System environment variables (System Environment Variables) ➔ User Environment Variables ➔ Registry Cache Configuration. If an enterprise user changes the authorization server, but the client still has the registry configuration of the old server, CAD It will first try to connect to the old service and cause an error. Use PowerShell Diagnostic scripts can perfectly eliminate such configuration dead ends.
Network delay and timeout mechanism (FLEXLM_TIMEOUT)
If the client is working remotely (remote dial-up VPN) Or the wireless network signal is unstable, FLEXlm’s default handshake response timeout (About 0.1 seconds) It may be too low. You can create a new file named FLEXLM_TIMEOUT system variable, the value is set to 1000000 (The unit is microseconds, that is 1.0 seconds), can effectively avoid network physical delays caused by -15 Connection failed.
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